task_url
stringlengths 30
116
| task_name
stringlengths 2
86
| task_description
stringlengths 0
14.4k
| language_url
stringlengths 2
53
| language_name
stringlengths 1
52
| code
stringlengths 0
61.9k
|
|---|---|---|---|---|---|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Ruby
|
Ruby
|
dict = File.readlines("unixdict.txt").collect(&:strip)
i = 0
res = dict.collect(&:reverse).sort.select do |z|
i += 1 while z > dict[i] and i < dict.length-1
z == dict[i] and z < z.reverse
end
puts "There are #{res.length} semordnilaps, of which the following are 5:"
res.take(5).each {|z| puts "#{z} #{z.reverse}"}
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Mathematica.2FWolfram_Language
|
Mathematica/Wolfram Language
|
SEDOL[Code_?(Function[v,StringFreeQ[v,{"A","E","I","O","U"}]])]:=
Code<>ToString[10-Mod[ToExpression[Quiet[Flatten[Characters[Code]
/.x_?LetterQ->(ToCharacterCode[x]-55)]]].{1,3,1,7,3,9},10]]
Scan[Print[SEDOL[#]] &, {"710889","B0YBKJ","406566","B0YBLH","228276","B0YBKL","557910","B0YBKR","585284","B0YBKT","B00030","DUMMY"}]
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#MUMPS
|
MUMPS
|
SEDOL
NEW A,B
SEDOL1
READ !,"Enter the first 6 digits of a SEDOL: ",A
SET B=$$SEDOLCHK(A)
WRITE !,$SELECT($LENGTH(B)=1:"Full SEDOL is "_A_B,1:B)
GOTO SEDOL1
QUIT
SEDOLCHK(STOCK)
NEW WT,VAL,I,CHK,C,FLAG
SET WT="1317391",VAL=0,FLAG=0
FOR I=1:1:6 SET C=$$TOUPPER($EXTRACT(STOCK,I)),VAL=VAL+($$SEDVAL(C)*$EXTRACT(WT,I)) SET:"AEIOUaeiou"[C FLAG=1
SET:$LENGTH(STOCK)'=6 FLAG=1
KILL WT,I,CHK,C
QUIT $SELECT(FLAG:"INVALID",'FLAG:(10-(VAL#10))#10)
SEDVAL(X)
QUIT $SELECT($ISVALIDNUM(X):X,1:$ASCII(X)-$ASCII("@")+9)
TOUPPER(X)
NEW UP,LO
SET UP="ABCDEFGHIJKLMNOPQRSTUVWXYZ",LO="abcdefghijklmnopqrstuvwxyz"
QUIT $TRANSLATE(X,LO,UP)
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Picat
|
Picat
|
go =>
println([f(I) : I in 1..22]),
nl,
check(1_000_000),
nl.
% The formula
f(N) = N + floor(1/2 + sqrt(N)).
check(Limit) =>
Squares = new_map([I*I=1:I in 1..sqrt(Limit)]),
Check = [[I,T] : I in 1..Limit-1, T=f(I), Squares.has_key(T)],
println(check=Check.len).
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#PicoLisp
|
PicoLisp
|
(de sqfun (N)
(+ N (sqrt N T)) ) # 'sqrt' rounds when called with 'T'
(for I 22
(println I (sqfun I)) )
(for I 1000000
(let (N (sqfun I) R (sqrt N))
(when (= N (* R R))
(prinl N " is square") ) ) )
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Maxima
|
Maxima
|
/* illustrating some functions on sets; names are self-explanatory */
a: {1, 2, 3, 4};
{1, 2, 3, 4}
b: {2, 4, 6, 8};
{2, 4, 6, 8}
intersection(a, b);
{2, 4}
union(a, b);
{1, 2, 3, 4, 6, 8}
powerset(a);
{{}, {1}, {1, 2}, {1, 2, 3}, {1, 2, 3, 4}, {1, 2, 4}, {1, 3}, {1, 3, 4}, {1, 4}, {2}, {2, 3}, {2, 3, 4}, {2, 4}, {3}, {3, 4}, {4}}
set_partitions(a);
{{{1}, {2}, {3}, {4}}, {{1}, {2}, {3, 4}}, {{1}, {2, 3}, {4}}, {{1}, {2, 3, 4}}, {{1}, {2, 4}, {3}}, {{1, 2}, {3}, {4}},
{{1, 2}, {3, 4}}, {{1, 2, 3}, {4}}, {{1, 2, 3, 4}}, {{1, 2, 4}, {3}}, {{1, 3}, {2}, {4}}, {{1, 3}, {2, 4}}, {{1, 3, 4}, {2}},
{{1, 4}, {2}, {3}}, {{1, 4}, {2, 3}}}
setdifference(a, b);
{1, 3}
emptyp(a);
false
elementp(2, a);
true
cardinality(a);
4
cartesian_product(a, b);
{[1, 2], [1, 4], [1, 6], [1, 8], [2, 2], [2, 4], [2, 6], [2, 8], [3, 2], [3, 4], [3, 6], [3, 8], [4, 2], [4, 4], [4, 6], [4, 8]}
subsetp(a, b);
false
symmdifference(a, b);
{1, 3, 6, 8}
partition_set(union(a, b), evenp);
[{1, 3}, {2, 4, 6, 8}]
c: setify(makelist(fib(n), n, 1, 20));
{1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765}
equiv_classes(c, lambda([m, n], mod(m - n, 3) = 0));
{{1, 13, 34, 55, 610, 1597, 2584}, {2, 5, 8, 89, 233, 377, 4181}, {3, 21, 144, 987, 6765}}
disjointp(a, b);
false
adjoin(7, a);
{1, 2, 3, 4, 7}
a;
{1, 2, 3, 4}
disjoin(1, a);
{2, 3, 4}
a;
{1, 2, 3, 4}
subset(c, primep);
{2, 3, 5, 13, 89, 233, 1597}
permutations(a);
{[1, 2, 3, 4], [1, 2, 4, 3], [1, 3, 2, 4], [1, 3, 4, 2], [1, 4, 2, 3], [1, 4, 3, 2],
[2, 1, 3, 4], [2, 1, 4, 3], [2, 3, 1, 4], [2, 3, 4, 1], [2, 4, 1, 3], [2, 4, 3, 1],
[3, 1, 2, 4], [3, 1, 4, 2], [3, 2, 1, 4], [3, 2, 4, 1], [3, 4, 1, 2], [3, 4, 2, 1],
[4, 1, 2, 3], [4, 1, 3, 2], [4, 2, 1, 3], [4, 2, 3, 1], [4, 3, 1, 2], [4, 3, 2, 1]}
setequalp(a, b);
false
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#EDSAC_order_code
|
EDSAC order code
|
[Sieve of Eratosthenes]
[EDSAC program. Initial Orders 2]
[Memory usage:
56..87 library subroutine P6, for printing
88..222 main program
224..293 mask table: 35 long masks; each has 34 1's and a single 0
294..1023 array of bits for integers 2, 3, 4, ...,
where bit is changed from 1 to 0 when integer is crossed out.
The address of the mask table must be even, and clear of the main program.
To change it, just change the value after "T47K" below.
The address of the bit array will then be changed automatically.]
[Subroutine M3, prints header, terminated by blank row of tape.
It's an "interlude", which runs and then gets overwritten.]
PFGKIFAFRDLFUFOFE@A6FG@E8FEZPF
@&*SIEVE!OF!ERATOSTHENES!#2020
@&*BASED!ON!CODE!BY!EIITI!WADA!#2001
..PZ
[Subroutine P6, prints strictly positive integer.
32 locations; working locations 1, 4, 5.]
T 56 K
GKA3FT25@H29@VFT4DA3@TFH30@S6@T1FV4DU4DAFG26@TFTF
O5FA4DF4FS4FL4FT4DA1FS3@G9@EFSFO31@E20@J995FJF!F
[Store address of mask table in (say) location 47
(chosen because its code letter M is first letter of "Mask").
Address must be even and clear of main program.]
T 47 K
P 224 F [<-------- address of mask table]
[Main program]
T 88 K [Define load address for main program.
Must be even, because of long values at start.]
G K [set @ (theta) for relative addressing]
[Long constants]
T#Z PF TZ [clears sandwich digit between 0 and 1]
[0] PD PF [long value 1; also low word = short 1]
T2#Z PF T2Z [clears sandwich digit between 2 and 3]
[2] PF K4096F [long value 1000...000 binary;
also high word = teleprinter null]
[Short constants
The address in the following C order is the (exclusive) end of the bit table.
Must be even: max = 1024, min = M + 72 where M is address of mask table set up above.
Usually 1024, but may be reduced, e.g. to make the program run faster.]
[4] C1024 D [or e.g. C 326 D to make it much faster]
[5] U F ['U' = 'T' - 'C']
[6] K F ['K' = 'S' - 'C']
[7] H #M [H order for start of mask table]
[8] H 70#M [used to test for end of mask table]
[9] P 2 F [constant4, or 2 in address field]
[10] P 70 F [constant 140, or 70 in address field]
[11] @ F [carriage return]
[12] & F [line feed]
[Short variables]
[13] P 1 F [p = number under test
Let p = 35*q + r, where 0 <= r < 35]
[14] P F [4*q]
[15] P 4 F [4*r]
[Initial values of orders; required only for optional code below.]
[16] C 70#M [initial value of a variable C order]
[17] T #M [initial value of a variable T order]
[18] T 70#M [initial value of a variable T order]
[19]
[Enter with acc = 0]
[Optional code to do some initializing at run time.
This code allows the program to run again without being loaded again.]
A 7 @ [initial values of variable orders]
T 65 @
A 16 @
T 66 @
A 17 @
T 44 @
A 18 @
T 52 @
[Initialize variables]
A @ [load 1 (short)]
L D [shift left 1]
U 13 @ [p := 2]
L 1 F [shift left 2]
T 15 @ [4*r := 8]
T 14 @ [4*q := 0]
[End of optional code]
[Make table of 35 masks 111...110, 111...101, ..., 011...111
Treat the mask 011...111 separately to avoid accumulator overflow.
Assume acc = 0 here.]
S #@ [acc all 1's]
S 2 #@ [acc := 0111...111]
[35] T 68 #M [store at high end of mask table]
S #@ [acc := -1]
L D [make mask 111...1110]
G 43 @ [jump to store it
[Loop shifting the mask right and storing the result in the mask table.
Uses first entry of bit array as temporary store.]
[39] T F [clear acc]
A 70 #M [load previous mask]
L D [shift left]
A #@ [add 1]
[43] U 70 #M [update current mask]
[44] T #M [store it in table (order changed at run time)]
A 44 @ [load preceding T order]
A 9 @ [inc address by 2]
U 44 @ [store back]
S 35 @ [reached high entry yet?]
G 39 @ [loop back if not]
[Mask table is now complete]
[Initialize bit array: no numbers crossed out, so all bits are 1]
[50] T F [clear acc]
S #@ [subtract long 1, make top 35 bits all 1's]
[52] T 70 #M [store as long value, both words all 1's (order changed at run time)]
A 52 @ [load preceding order]
A 9 @ [add 2 to address field]
U 52 @ [and store back]
S 5 @ [convert to C order with same address (*)]
S 4 @ [test for end of bit array]
G 50 @ [loop until stored all 1's in bit table]
[(*) Done so that end of bit table can be stored at one place only
in list of constants, i.e. 'C m D' only, not 'T m D' as well.]
[Start of main loop.]
[Testing whether number has been crossed out]
[59] T F [acc := 0]
A 66 @ [deriving S order from C order]
A 6 @
T 64 @
S #@ [acc := -1]
[64] S F [acc := 1's complement of bit-table entry (order changed at run time)]
[65] H #M [mult reg := start of mask array (order changed at run time)]
[66] C 70#M [acc := -1 iff p (current number) is crossed out (order changed at run time)]
[The next order is to avoid accumulator overflow if acc = max positive number]
E 70 @ [if acc >= 0, jump to process new prime]
A #@ [if acc < 0, add 1 to test for -1]
E 106 @ [if acc now >= 0 number is crossed out, jump to test next]
[Here if new prime found.
Send it to the teleprinter]
[70] O 11 @ [print CR]
O 12 @ [print LF]
T F [clear acc]
A 13 @ [load prime]
T F [store in C(0) for print routine]
A 75 @ [for subroutine return]
G 56 F [print prime]
[Cross out its multiples by setting corresponding bits to 0]
A 65 @ [load H order above]
T 102 @ [plant in crossing-out loop]
A 66 @ [load C order above]
T1 03 @ [plant in crossing-out loop]
[Start of crossing-out loop. Here acc must = 0]
[81] A 102 @ [load H order below]
A 15 @ [inc address field by 2*r, where p = 35q + r]
U 102 @ [update H order]
S 8 @ [compare with 'H 70 #M']
G 93 @ [skip if not gone beyond end of mask table]
T F [wrap mask address and inc address in bit tsble]
A 102 @ [load H order below]
S 10 @ [reduce mask address by 70]
T 102 @ [update H order]
A 103 @ [load C order below]
A 9 @ [add 2 to address]
T 103 @ [update C order]
[93] T F [clear acc]
A 103 @ [load C order below]
A 14 @ [inc address field by 2*q, where p = 35q + r]
U 103 @ [update C order]
S 4 @ [test for end of bit array]
E 106 @ [if finished crossing out, loop to test next number]
A 4 @ [restore C order]
A 5 @ [make T order with same address]
T 104 @ [store below]
[Execute the crossing-out orders created above]
[102] X F [mult reg := mask (order created at run time)]
[103] X F [acc := logical and with bit-table entry (order created at run time)]
[104] X F [update entry (order created at run time)]
E 81 @ [loop back with acc = 0]
[106] T F [clear acc]
A 13 @ [load p = number under test]
A @ [add 1 (single)]
T 13 @ [update]
A 15 @ [load 4*r, where p = 35q + r]
A 9 @ [add 4]
U 15 @ [store back (r inc'd by 1)]
S 10 @ [is 4*r now >= 140?]
G 119 @ [no, skip]
T 15 @ [yes, reduce 4*r by 140]
A 14 @ [load 4*q]
A 9 @ [add 4]
T 14 @ [store back (q inc'd by 1)]
[119] T F [clear acc]
A 65 @ [load 'H ... D' order, which refers to a mask]
A 9 @ [inc mask address by 2]
U 65 @ [update order]
S 8 @ [over end of mask table?]
G 59 @ [no, skip wrapround code]
A 7 @ [yes, add constant to wrap round]
T 65 @ [update H order]
A 66 @
A 9 @ [inc address by 2]
U 66 @ [and store back]
S 4 @ [test for end, as defined by C order at start]
G 59 @ [loop back if not at end]
[Finished whole thing]
[132] O 3 @ [output null to flush teleprinter buffer]
Z F [stop]
E 19 Z [address to start execution]
P F [acc = 0 at start]
|
http://rosettacode.org/wiki/Sierpinski_carpet
|
Sierpinski carpet
|
Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
######### #########
# ## ## # # ## ## #
######### #########
### ### ### ###
# # # # # # # #
### ### ### ###
######### #########
# ## ## # # ## ## #
######### #########
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
The use of the # character is not rigidly required for ASCII art.
The important requirement is the placement of whitespace and non-whitespace characters.
Related task
Sierpinski triangle
|
#zkl
|
zkl
|
fcn drawPat(x0,y0,s,img){ // Draw 3x3 pattern with hole in middle
foreach y,x in (3,3){
if(x.isEven or y.isEven){ // don't draw middle pattern
if(s>1) self.fcn(x*s + x0, y*s + y0, s/3, img); // recurse
else img[x + x0, y + y0]=0xff0000; // red
}
}
}
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Rust
|
Rust
|
use std::collections::HashSet;
use std::fs::File;
use std::io::{self, BufRead};
use std::iter::FromIterator;
fn semordnilap(filename: &str) -> std::io::Result<()> {
let file = File::open(filename)?;
let mut seen = HashSet::new();
let mut count = 0;
for line in io::BufReader::new(file).lines() {
let mut word = line?;
word.make_ascii_lowercase();
let rev = String::from_iter(word.chars().rev());
if seen.contains(&rev) {
if count < 5 {
println!("{}\t{}", word, rev);
}
count += 1;
} else {
seen.insert(word);
}
}
println!("\nSemordnilap pairs found: {}", count);
Ok(())
}
fn main() {
match semordnilap("unixdict.txt") {
Ok(()) => {}
Err(error) => eprintln!("{}", error),
}
}
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Scala
|
Scala
|
val wordsAll =
scala.io.Source.
fromURL("http://wiki.puzzlers.org/pub/wordlists/unixdict.txt").
getLines().map(_.toLowerCase).toIndexedSeq
/**
* Given a sequence of lower-case words return a sub-sequence
* of matches containing the word and its reverse if the two
* words are different.
*/
def semordnilap( words:IndexedSeq[String] ) : IndexedSeq[(String,String)] = {
words.
zipWithIndex. // index will be needed to eliminate duplicate
filter {
case (w,i) =>
val j = words.indexOf(w.reverse) // eg. (able,62) and (elba,7519)
i < j && w != w.reverse // save the matches which are not palindromes
}.
map {
case (w,_) => (w,w.reverse) // drop the index
}
}
val ss = semordnilap(wordsAll)
{
println( s"${ss.size} matches, including: \n" )
println( ss.take(5).mkString( "\n" ) )
}
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Nim
|
Nim
|
proc c2v(c: char): int =
assert c notin "AEIOU"
if c < 'A': ord(c) - ord('0') else: ord(c) - ord('7')
const weight = [1, 3, 1, 7, 3, 9]
proc checksum(sedol: string): char =
var val = 0
for i, ch in sedol:
val += c2v(ch) * weight[i]
result = chr((10 - val mod 10) mod 10 + ord('0'))
for sedol in ["710889", "B0YBKJ", "406566", "B0YBLH",
"228276", "B0YBKL", "557910", "B0YBKR",
"585284", "B0YBKT", "B00030"]:
echo sedol, " → ", sedol & checksum(sedol)
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#OCaml
|
OCaml
|
let char2value c =
assert (not (String.contains "AEIOU" c));
match c with
| '0'..'9' -> int_of_char c - int_of_char '0'
| 'A'..'Z' -> int_of_char c - int_of_char 'A' + 10
| _ -> assert false
let sedolweight = [1;3;1;7;3;9]
let explode s =
s |> String.to_seq |> List.of_seq
let checksum sedol =
let tmp = List.fold_left2 (fun sum ch weight -> sum + char2value ch * weight)
0 (explode sedol) sedolweight in
string_of_int ((10 - (tmp mod 10)) mod 10) ;;
List.iter (fun sedol -> print_endline (sedol ^ checksum sedol))
[ "710889";
"B0YBKJ";
"406566";
"B0YBLH";
"228276";
"B0YBKL";
"557910";
"B0YBKR";
"585284";
"B0YBKT" ]
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#PL.2FI
|
PL/I
|
put skip edit ((n, n + floor(sqrt(n) + 0.5) do n = 1 to n))
(skip, 2 f(5));
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#PostScript
|
PostScript
|
/nonsquare { dup sqrt .5 add floor add } def
/issquare { dup sqrt floor dup mul eq } def
1 1 22 { nonsquare = } for
1 1 1000 {
dup nonsquare issquare {
(produced a square!) = = exit
} if pop
} for
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Nanoquery
|
Nanoquery
|
class set
declare internal_list
def set()
internal_list = list()
end
def set(list)
internal_list = list
end
def append(value)
if not value in internal_list
internal_list.append(value)
end
return this
end
def contains(value)
return value in internal_list
end
def difference(other)
diff = list()
for value in this.internal_list
diff.append(value)
end
for i in range(len(diff) - 1, 0)
if diff[i] in other.internal_list
diff.remove(i)
end
end
return new(set, diff)
end
def operator=(other)
for value in other.internal_list
if not value in this.internal_list
return false
end
end
return true
end
def intersection(other)
intersect = list()
for value in this.internal_list
if other.contains(value)
intersect.append(value)
end
end
return new(set, intersect)
end
def subset(other)
for value in this.internal_list
if not value in other.internal_list
return false
end
end
return true
end
def union(other)
u = list()
for value in this.internal_list
u.append(value)
end
for value in other.internal_list
if not value in u
u.append(value)
end
end
return new(set, u)
end
def toString()
return str(this.internal_list)
end
end
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Eiffel
|
Eiffel
|
class
APPLICATION
create
make
feature
make
-- Run application.
do
across primes_through (100) as ic loop print (ic.item.out + " ") end
end
primes_through (a_limit: INTEGER): LINKED_LIST [INTEGER]
-- Prime numbers through `a_limit'
require
valid_upper_limit: a_limit >= 2
local
l_tab: ARRAY [BOOLEAN]
do
create Result.make
create l_tab.make_filled (True, 2, a_limit)
across
l_tab as ic
loop
if ic.item then
Result.extend (ic.target_index)
across ((ic.target_index * ic.target_index) |..| l_tab.upper).new_cursor.with_step (ic.target_index) as id
loop
l_tab [id.item] := False
end
end
end
end
end
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Seed7
|
Seed7
|
$ include "seed7_05.s7i";
include "gethttp.s7i";
const func string: reverse (in string: word) is func
result
var string: drow is "";
local
var integer: index is 0;
begin
for index range length(word) downto 1 do
drow &:= word[index];
end for;
end func;
const proc: main is func
local
var array string: wordList is 0 times "";
var set of string: words is (set of string).value;
var string: word is "";
var string: drow is "";
var integer: count is 0;
begin
wordList := split(lower(getHttp("www.puzzlers.org/pub/wordlists/unixdict.txt")), "\n");
for word range wordList do
drow := reverse(word);
if drow not in words then
incl(words, word);
else
if count < 5 then
writeln(word <& " " <& drow);
end if;
incr(count);
end if;
end for;
writeln;
writeln("Semordnilap pairs: " <& count);
end func;
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Sidef
|
Sidef
|
var c = 0
var seen = Hash()
ARGF.each { |line|
line.chomp!
var r = line.reverse
((seen{r} := 0 ++) && (c++ < 5) && say "#{line} #{r}") ->
|| (seen{line} := 0 ++)
}
say c
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Oforth
|
Oforth
|
func: sedol(s)
[ 1, 3, 1, 7, 3, 9 ] s
zipWith(#[ dup isDigit ifTrue: [ '0' - ] else: [ 'A' - 10 + ] * ]) sum
10 mod 10 swap - 10 mod
StringBuffer new s << swap '0' + <<c ;
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Pascal
|
Pascal
|
program Sedols(output);
function index(c: char): integer;
const
alpha = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
var
i: integer;
begin
index := 0;
for i := low(alpha) to high(alpha) do
if c = alpha[i] then
index := i;
end;
function checkdigit(c: string): char;
const
weight: array [1..6] of integer = (1, 3, 1, 7, 3, 9);
var
i, sum: integer;
begin
sum := 0;
for i := 1 to 6 do
sum := sum + (index(c[i]) - 1) * weight[i];
checkdigit := char((10 - (sum mod 10)) mod 10 + 48);
end;
const
codes: array [1..11] of string =
('710889', 'B0YBKJ', '406566', 'B0YBLH',
'228276', 'B0YBKL', '557910', 'B0YBKR',
'585284', 'B0YBKT', 'B00030');
var
seforl: string;
i: integer;
begin
for i := low(codes) to high(codes) do
begin
seforl := codes[i];
setlength(seforl, 7);
seforl[7] := checkdigit(codes[i]);
writeln(codes[i], ' -> ', seforl);
end;
end.
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#PowerShell
|
PowerShell
|
filter Get-NonSquare {
return $_ + [Math]::Floor(1/2 + [Math]::Sqrt($_))
}
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#PureBasic
|
PureBasic
|
OpenConsole()
For a = 1 To 22
; Integer, so no floor needed
tmp = 1 / 2 + Sqr(a)
Print(Str(a + tmp) + ", ")
Next
PrintN("")
PrintN("Starting check till one million")
For a = 1 To 1000000
value.d = a + Round((1 / 2 + Sqr(a)), #PB_Round_Down)
root = Sqr(value)
If value - root*root = 0
found + 1
If found < 20
PrintN("Found a square! " + Str(value))
ElseIf found = 20
PrintN("And more")
EndIf
EndIf
Next
If found
PrintN(Str(found) + " Squares found, see above")
Else
PrintN("No squares, all ok")
EndIf
; Wait for enter
Input()
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Nemerle
|
Nemerle
|
using System.Console;
using Nemerle.Collections;
module RCSet
{
HasSubset[T](this super : Set[T], sub : Set[T]) : bool
{
super.ForAll(x => sub.Contains(x))
}
Main() : void
{
def names1 = Set(["Bob", "Billy", "Tom", "Dick", "Harry"]);
def names2 = Set(["Bob", "Mary", "Alice", "Louisa"]);
//def names3 = Set(["Bob", "Bob"]); // unfortunately, duplicated elements are not well handled by the stock
// implementation, this statement would throw an ArgumentException
def elem = names1.Contains("Bob"); // element test
def names1u2 = names1.Sum(names2); // union
def names1d2 = names1.Subtract(names2); // difference
def names1i2 = names1.Intersect(names2); // intersection
def same = names1.Equals(names2); // equality
def sub12 = names1.HasSubset(names2); // subset
WriteLine($"$names1u2\n$names1d2\n$names1i2");
WriteLine($"$same\t$sub12");
}
}
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Elixir
|
Elixir
|
defmodule Prime do
def eratosthenes(limit \\ 1000) do
sieve = [false, false | Enum.to_list(2..limit)] |> List.to_tuple
check_list = [2 | Stream.iterate(3, &(&1+2)) |> Enum.take(round(:math.sqrt(limit)/2))]
Enum.reduce(check_list, sieve, fn i,tuple ->
if elem(tuple,i) do
clear_num = Stream.iterate(i*i, &(&1+i)) |> Enum.take_while(fn x -> x <= limit end)
clear(tuple, clear_num)
else
tuple
end
end)
end
defp clear(sieve, list) do
Enum.reduce(list, sieve, fn i, acc -> put_elem(acc, i, false) end)
end
end
limit = 199
sieve = Prime.eratosthenes(limit)
Enum.each(0..limit, fn n ->
if x=elem(sieve, n), do: :io.format("~3w", [x]), else: :io.format(" .")
if rem(n+1, 20)==0, do: IO.puts ""
end)
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#SNOBOL4
|
SNOBOL4
|
* Program: semordnilap.sbl
* To run: sbl semordnilap.sbl < unixdict.txt
* Description: A semordnilap is a word (or phrase) that spells
* a different word (or phrase) backward. "Semordnilap"
* is a word that itself is a semordnilap.
* Example: lager and regal
* Reads file unixdict.txt
* Comment: Tested using the Spitbol for Linux version of SNOBOL4
output = "Some Semordnilap Pairs from File unixdict.txt"
atable = table(25200,,-1)
ntable = table(25200,,-2)
* Read dictionary file into memory
in1
word = input :f(p1)
count = count + 1
atable[word] = word
ntable[count] = word
:(in1)
* Process dictionary to find unique semordnilaps
p1
i = lt(i,count) i + 1 :f(p2)
newword = atable[reverse(ntable[i])]
leq(newword,-1) :s(p1)
ident(ntable[i],newword) :s(p1)
output = lt(outcount,5) ntable[i] ', ' newword
atable[ntable[i]] = atable[newword] = -1
outcount = outcount + 1
:(p1)
p2
output = 'The number of semordnilap pairs is: ' outcount
END
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Stata
|
Stata
|
set seed 17760704
import delimited http://www.puzzlers.org/pub/wordlists/unixdict.txt, clear
save temp, replace
replace v1=strreverse(v1)
merge 1:1 v1 using temp, nogen keep(3)
drop if v1>=strreverse(v1)
count
158
sample 5, count
gen v2=strreverse(v1)
list, noheader noobs
+-------------+
| evil live |
| pat tap |
| at ta |
| nit tin |
| ku uk |
+-------------+
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Perl
|
Perl
|
use List::Util qw(sum);
use POSIX qw(strtol);
sub zip(&\@\@) {
my $f = shift;
my @a = @{shift()};
my @b = @{shift()};
my @result;
push(@result, $f->(shift @a, shift @b)) while @a && @b;
return @result;
}
my @weights = (1, 3, 1, 7, 3, 9);
sub sedol($) {
my $s = shift;
$s =~ /[AEIOU]/ and die "No vowels";
my @vs = map {(strtol $_, 36)[0]} split //, $s;
my $checksum = sum (zip {$_[0] * $_[1]} @vs, @weights);
my $check_digit = (10 - $checksum % 10) % 10;
return $s . $check_digit;
}
while (<>) {
chomp;
print sedol($_), "\n";
}
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Python
|
Python
|
>>> from math import floor, sqrt
>>> def non_square(n):
return n + floor(1/2 + sqrt(n))
>>> # first 22 values has no squares:
>>> print(*map(non_square, range(1, 23)))
2 3 5 6 7 8 10 11 12 13 14 15 17 18 19 20 21 22 23 24 26 27
>>> # The following check shows no squares up to one million:
>>> def is_square(n):
return sqrt(n).is_integer()
>>> non_squares = map(non_square, range(1, 10 ** 6))
>>> next(filter(is_square, non_squares))
StopIteration Traceback (most recent call last)
<ipython-input-45-f32645fc1c0a> in <module>()
1 non_squares = map(non_square, range(1, 10 ** 6))
----> 2 next(filter(is_square, non_squares))
StopIteration:
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Nim
|
Nim
|
var # creation
s = {0, 3, 5, 10}
t = {3..20, 50..55}
if 5 in s: echo "5 is in!" # element test
var
c = s + t # union
d = s * t # intersection
e = s - t # difference
if s <= t: echo "s ⊆ t" # subset
if s < t: echo "s ⊂ t" # strong subset
if s == t: echo "s = s" # equality
s.incl(4) # add 4 to set
s.excl(5) # remove 5 from set
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Elm
|
Elm
|
module Main exposing (main)
import Browser exposing (element)
import Task exposing (Task, succeed, perform, andThen)
import Html exposing (Html, div, text)
import Time exposing (now, posixToMillis)
type CIS a = CIS a (() -> CIS a)
uptoCIS2List : comparable -> CIS comparable -> List comparable
uptoCIS2List n cis =
let loop (CIS hd tl) lst =
if hd > n then List.reverse lst
else loop (tl()) (hd :: lst)
in loop cis []
countCISTo : comparable -> CIS comparable -> Int
countCISTo n cis =
let loop (CIS hd tl) cnt =
if hd > n then cnt else loop (tl()) (cnt + 1)
in loop cis 0
primesTreeFolding : () -> CIS Int
primesTreeFolding() =
let
merge (CIS x xtl as xs) (CIS y ytl as ys) =
case compare x y of
LT -> CIS x <| \ () -> merge (xtl()) ys
EQ -> CIS x <| \ () -> merge (xtl()) (ytl())
GT -> CIS y <| \ () -> merge xs (ytl())
pmult bp =
let adv = bp + bp
pmlt p = CIS p <| \ () -> pmlt (p + adv)
in pmlt (bp * bp)
allmlts (CIS bp bptl) =
CIS (pmult bp) <| \ () -> allmlts (bptl())
pairs (CIS frst tls) =
let (CIS scnd tlss) = tls()
in CIS (merge frst scnd) <| \ () -> pairs (tlss())
cmpsts (CIS (CIS hd tl) tls) =
CIS hd <| \ () -> merge (tl()) <| cmpsts <| pairs (tls())
testprm n (CIS hd tl as cs) =
if n < hd then CIS n <| \ () -> testprm (n + 2) cs
else testprm (n + 2) (tl())
oddprms() =
CIS 3 <| \ () -> testprm 5 <| cmpsts <| allmlts <| oddprms()
in CIS 2 <| \ () -> oddprms()
type alias Model = ( Int, String, String )
type Msg = Start Int | Done ( Int, Int )
cLIMIT : Int
cLIMIT = 1000000
timemillis : () -> Task Never Int
timemillis() = now |> andThen (\ t -> succeed (posixToMillis t))
test : Int -> Cmd Msg
test lmt =
let cnt = countCISTo lmt (primesTreeFolding()) -- (soeDict())
in timemillis() |> andThen (\ t -> succeed ( t, cnt )) |> perform Done
myupdate : Msg -> Model -> (Model, Cmd Msg)
myupdate msg mdl =
let (strttm, oldstr, _) = mdl in
case msg of
Start tm -> ( ( tm, oldstr, "Running..." ), test cLIMIT )
Done (stptm, answr) ->
( ( stptm, oldstr, "Found " ++ String.fromInt answr ++
" primes to " ++ String.fromInt cLIMIT ++
" in " ++ String.fromInt (stptm - strttm) ++ " milliseconds." )
, Cmd.none )
myview : Model -> Html msg
myview mdl =
let (_, str1, str2) = mdl
in div [] [ div [] [text str1], div [] [text str2] ]
main : Program () Model Msg
main =
element { init = \ _ -> ( ( 0
, "The primes up to 100 are: " ++
(primesTreeFolding() |> uptoCIS2List 100
|> List.map String.fromInt
|> String.join ", ") ++ "."
, "" ), perform Start (timemillis()) )
, update = myupdate
, subscriptions = \ _ -> Sub.none
, view = myview }
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#SuperCollider
|
SuperCollider
|
(
var text, words, sdrow, semordnilap, selection;
File.use("unixdict.txt".resolveRelative, "r", { |f| x = text = f.readAllString });
words = text.split(Char.nl).collect { |each| each.asSymbol };
sdrow = text.reverse.split(Char.nl).collect { |each| each.asSymbol };
semordnilap = sect(words, sdrow); // converted to symbols so intersection is possible
semordnilap = semordnilap.collect { |each| each.asString };
"There are % in unixdict.txt\n".postf(semordnilap.size);
"For example those, with more than 3 characters:".postln;
selection = semordnilap.select { |each| each.size >= 4 }.scramble.keep(4);
selection.do { |each| "% %\n".postf(each, each.reverse); };
)
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Phix
|
Phix
|
type string6(object s)
return string(s) and length(s)=6
end type
type sedolch(integer ch)
return ch>='0' and ch<='Z' and (ch<='9' or ch>='A') and not find(ch,"AEIOU")
end type
function sedol(string6 t)
sedolch c
integer s = 0
for i=1 to 6 do
c = t[i]
s += iff(c>='A'?c-'A'+10:c-'0')*{1,3,1,7,3,9}[i]
end for
return t & mod(10-mod(s,10),10)+'0'
end function
constant tests = {"710889",
"B0YBKJ",
"406566",
"B0YBLH",
"228276",
"B0YBKL",
"557910",
"B0YBKR",
"585284",
"B0YBKT",
"B00030"}
for i=1 to length(tests) do
?sedol(tests[i])
end for
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Quackery
|
Quackery
|
$ "bigrat.qky" loadfile
[ dup n->v 2 vsqrt
drop 1 2 v+ / + ] is nonsquare ( n --> n )
[ sqrt nip 0 = ] is squarenum ( n --> b )
say "Non-squares: "
22 times [ i^ 1+ nonsquare echo sp ]
cr cr
0
999999 times
[ i^ 1+ nonsquare
squarenum if 1+ ]
echo say " square numbers found"
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#R
|
R
|
nonsqr <- function(n) n + floor(1/2 + sqrt(n))
nonsqr(1:22)
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Objective-C
|
Objective-C
|
#import <Foundation/Foundation.h>
int main (int argc, const char *argv[]) {
@autoreleasepool {
NSSet *s1 = [NSSet setWithObjects:@"a", @"b", @"c", @"d", @"e", nil];
NSSet *s2 = [NSSet setWithObjects:@"b", @"c", @"d", @"e", @"f", @"h", nil];
NSSet *s3 = [NSSet setWithObjects:@"b", @"c", @"d", nil];
NSSet *s4 = [NSSet setWithObjects:@"b", @"c", @"d", nil];
NSLog(@"s1: %@", s1);
NSLog(@"s2: %@", s2);
NSLog(@"s3: %@", s3);
NSLog(@"s4: %@", s4);
// Membership
NSLog(@"b in s1: %d", [s1 containsObject:@"b"]);
NSLog(@"f in s1: %d", [s1 containsObject:@"f"]);
// Union
NSMutableSet *s12 = [NSMutableSet setWithSet:s1];
[s12 unionSet:s2];
NSLog(@"s1 union s2: %@", s12);
// Intersection
NSMutableSet *s1i2 = [NSMutableSet setWithSet:s1];
[s1i2 intersectSet:s2];
NSLog(@"s1 intersect s2: %@", s1i2);
// Difference
NSMutableSet *s1_2 = [NSMutableSet setWithSet:s1];
[s1_2 minusSet:s2];
NSLog(@"s1 - s2: %@", s1_2);
// Subset of
NSLog(@"s3 subset of s1: %d", [s3 isSubsetOfSet:s1]);
// Equality
NSLog(@"s3 = s4: %d", [s3 isEqualToSet:s4]);
// Cardinality
NSLog(@"size of s1: %lu", [s1 count]);
// Has intersection (not disjoint)
NSLog(@"does s1 intersect s2? %d", [s1 intersectsSet:s2]);
// Adding and removing elements from a mutable set
NSMutableSet *mut_s1 = [NSMutableSet setWithSet:s1];
[mut_s1 addObject:@"g"];
NSLog(@"mut_s1 after adding g: %@", mut_s1);
[mut_s1 addObject:@"b"];
NSLog(@"mut_s1 after adding b again: %@", mut_s1);
[mut_s1 removeObject:@"c"];
NSLog(@"mut_s1 after removing c: %@", mut_s1);
}
return 0;
}
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Emacs_Lisp
|
Emacs Lisp
|
(defun sieve-set (limit)
(let ((xs (make-vector (1+ limit) 0)))
(cl-loop for i from 2 to limit
when (zerop (aref xs i))
collect i
and do (cl-loop for m from (* i i) to limit by i
do (aset xs m 1)))))
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Swift
|
Swift
|
guard let data = try? String(contentsOfFile: "unixdict.txt") else {
fatalError()
}
let words = Set(data.components(separatedBy: "\n"))
let pairs = words
.map({ ($0, String($0.reversed())) })
.filter({ $0.0 < $0.1 && words.contains($0.1) })
print("Found \(pairs.count) pairs")
print("Five examples: \(pairs.prefix(5))")
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#PHP
|
PHP
|
function char2value($c) {
assert(stripos('AEIOU', $c) === FALSE);
return intval($c, 36);
}
$sedolweight = array(1,3,1,7,3,9);
function checksum($sedol) {
global $sedolweight;
$tmp = array_sum(array_map(create_function('$ch, $weight', 'return char2value($ch) * $weight;'),
str_split($sedol), $sedolweight)
);
return strval((10 - ($tmp % 10)) % 10);
}
foreach (array('710889',
'B0YBKJ',
'406566',
'B0YBLH',
'228276',
'B0YBKL',
'557910',
'B0YBKR',
'585284',
'B0YBKT') as $sedol)
echo $sedol, checksum($sedol), "\n";
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Racket
|
Racket
|
#lang racket
(define (non-square n)
(+ n (exact-floor (+ 1/2 (sqrt n)))))
(map non-square (range 1 23))
(define (square? n) (integer? (sqrt n)))
(for/or ([n (in-range 1 1000001)])
(square? (non-square n)))
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Raku
|
Raku
|
sub nth-term (Int $n) { $n + round sqrt $n }
# Print the first 22 values of the sequence
say (nth-term $_ for 1 .. 22);
# Check that the first million values of the sequence are indeed non-square
for 1 .. 1_000_000 -> $i {
say "Oops, nth-term($i) is square!" if (sqrt nth-term $i) %% 1;
}
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#OCaml
|
OCaml
|
# module IntSet = Set.Make(struct type t = int let compare = compare end);; (* Create a module for our type of set *)
module IntSet :
sig
type elt = int
type t
val empty : t
val is_empty : t -> bool
val mem : elt -> t -> bool
val add : elt -> t -> t
val singleton : elt -> t
val remove : elt -> t -> t
val union : t -> t -> t
val inter : t -> t -> t
val diff : t -> t -> t
val compare : t -> t -> int
val equal : t -> t -> bool
val subset : t -> t -> bool
val iter : (elt -> unit) -> t -> unit
val fold : (elt -> 'a -> 'a) -> t -> 'a -> 'a
val for_all : (elt -> bool) -> t -> bool
val exists : (elt -> bool) -> t -> bool
val filter : (elt -> bool) -> t -> t
val partition : (elt -> bool) -> t -> t * t
val cardinal : t -> int
val elements : t -> elt list
val min_elt : t -> elt
val max_elt : t -> elt
val choose : t -> elt
val split : elt -> t -> t * bool * t
val find : elt -> t -> elt
val of_list : elt list -> t
end
# IntSet.empty;; (* Empty set. A set is an abstract type that will not display in the interpreter *)
- : IntSet.t = <abstr>
# IntSet.elements (IntSet.empty);; (* Get the previous set into a list *)
- : IntSet.elt list = []
# let s1 = IntSet.of_list [1;2;3;4;3];;
val s1 : IntSet.t = <abstr>
# IntSet.elements s1;;
- : IntSet.elt list = [1; 2; 3; 4]
# let s2 = IntSet.of_list [3;4;5;6];;
val s2 : IntSet.t = <abstr>
# IntSet.elements s2;;
- : IntSet.elt list = [3; 4; 5; 6]
# IntSet.elements (IntSet.union s1 s2);; (* Union *)
- : IntSet.elt list = [1; 2; 3; 4; 5; 6]
# IntSet.elements (IntSet.inter s1 s2);; (* Intersection *)
- : IntSet.elt list = [3; 4]
# IntSet.elements (IntSet.diff s1 s2);; (* Difference *)
- : IntSet.elt list = [1; 2]
# IntSet.subset s1 s1;; (* Subset *)
- : bool = true
# IntSet.subset (IntSet.of_list [3;1]) s1;;
- : bool = true
# IntSet.equal (IntSet.of_list [3;2;4;1]) s1;; (* Equality *)
- : bool = true
# IntSet.equal s1 s2;;
- : bool = false
# IntSet.mem 2 s1;; (* Membership *)
- : bool = true
# IntSet.mem 10 s1;;
- : bool = false
# IntSet.cardinal s1;; (* Cardinality *)
- : int = 4
# IntSet.elements (IntSet.add 99 s1);; (* Create a new set by inserting *)
- : IntSet.elt list = [1; 2; 3; 4; 99]
# IntSet.elements (IntSet.remove 3 s1);; (* Create a new set by deleting *)
- : IntSet.elt list = [1; 2; 4]
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Erlang
|
Erlang
|
-module( sieve_of_eratosthenes ).
-export( [primes_upto/1] ).
primes_upto( N ) ->
Ns = lists:seq( 2, N ),
Dict = dict:from_list( [{X, potential_prime} || X <- Ns] ),
{Upto_sqrt_ns, _T} = lists:split( erlang:round(math:sqrt(N)), Ns ),
{N, Prime_dict} = lists:foldl( fun find_prime/2, {N, Dict}, Upto_sqrt_ns ),
lists:sort( dict:fetch_keys(Prime_dict) ).
find_prime( N, {Max, Dict} ) -> find_prime( dict:find(N, Dict), N, {Max, Dict} ).
find_prime( error, _N, Acc ) -> Acc;
find_prime( {ok, _Value}, N, {Max, Dict} ) when Max > N*N ->
{Max, lists:foldl( fun dict:erase/2, Dict, lists:seq(N*N, Max, N))};
find_prime( {ok, _Value}, _, R) -> R.
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Tcl
|
Tcl
|
package require Tcl 8.5
package require http
# Fetch the words
set t [http::geturl http://www.puzzlers.org/pub/wordlists/unixdict.txt]
set wordlist [split [http::data $t] \n]
http::cleanup $t
# Build hash table for speed
foreach word $wordlist {
set reversed([string reverse $word]) "dummy"
}
# Find where a reversal exists
foreach word $wordlist {
if {[info exists reversed($word)] && $word ne [string reverse $word]} {
# Remove to prevent pairs from being printed twice
unset reversed([string reverse $word])
# Add to collection of pairs
set pairs($word/[string reverse $word]) "dummy"
}
}
set pairlist [array names pairs] ;# NB: pairs are in *arbitrary* order
# Report what we've found
puts "Found [llength $pairlist] reversed pairs"
foreach pair $pairlist {
puts "Example: $pair"
if {[incr i]>=5} break
}
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#PicoLisp
|
PicoLisp
|
(de sedol (Str)
(pack Str
(char
(+ `(char "0")
(%
(- 10
(%
(sum
'((W C)
(cond
((>= "9" C "0")
(* W (format C)) )
((>= "Z" (setq C (uppc C)) "A")
(* W (+ 10 (- (char C) `(char "A")))) ) ) )
(1 3 1 7 3 9)
(chop Str) )
10 ) )
10 ) ) ) ) )
(for S '("710889" "B0YBKJ" "406566" "B0YBLH" "228276" "B0YBKL" "557910" "B0YBKR" "585284" "B0YBKT" "B00030")
(prinl (sedol S)) )
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Red
|
Red
|
Red ["Sequence of non-squares"]
repeat i 999'999 [
n: i + round/floor 0.5 + sqrt i
if i < 23 [prin [to-integer n ""]]
if equal? round/floor n sqrt n [
print "Square found!"
break
]
]
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#REXX
|
REXX
|
/*REXX pgm displays some non─square numbers, & also displays a validation check up to 1M*/
parse arg N M . /*obtain optional arguments from the CL*/
if N=='' | N=="," then N= 22 /*Not specified? Then use the default.*/
if M=='' | M=="," then M= 1000000 /* " " " " " " */
say 'The first ' N " non─square numbers:" /*display a header of what's to come. */
say /* [↑] default for M is one million.*/
say center('index', 20) center("non─square numbers", 20)
say center('' , 20, "═") center('' , 20, "═")
do j=1 for N
say center(j, 20) center(j +floor(1/2 +sqrt(j)), 20)
end /*j*/
#= 0
do k=1 for M /*have it step through a million of 'em*/
$= k + floor( sqrt(k) + .5 ) /*use the specified formula (algorithm)*/
iRoot= iSqrt($) /*··· and also use the ISQRT function.*/
if iRoot * iRoot == $ then #= # + 1 /*have we found a mistook? (sic) */
end /*k*/
say; if #==0 then #= 'no' /*use gooder English for display below.*/
say 'Using the formula: floor[ 1/2 + sqrt(n) ], ' # " squares found up to " M'.'
/* [↑] display (possible) error count.*/
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
floor: parse arg floor_; return trunc( floor_ - (floor_ < 0) )
/*──────────────────────────────────────────────────────────────────────────────────────*/
iSqrt: procedure; parse arg x; #=1; r= 0; do while # <= x; #= #*4; end
do while #>1; #=#%4; _=x-r-#; r=r%2; if _<0 then iterate; x=_; r=r+#; end; return r
/*──────────────────────────────────────────────────────────────────────────────────────*/
sqrt: procedure; parse arg x; if x=0 then return 0; d=digits(); m.=9; numeric form; h=d+6
numeric digits; parse value format(x,2,1,,0) 'E0' with g 'E' _ .; g=g *.5'e'_%2
do j=0 while h>9; m.j= h; h= h % 2 + 1; end /*j*/
do k=j+5 to 0 by -1; numeric digits m.k; g= (g+x/g)*.5; end /*k*/; return g
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Ol
|
Ol
|
; test set
(define set1 '(1 2 3 4 5 6 7 8 9))
(define set2 '(3 4 5 11 12 13 14))
(define set3 '(4 5 6 7))
(define set4 '(1 2 3 4 5 6 7 8 9))
; union
(print (union set1 set2))
; ==> (1 2 6 7 8 9 3 4 5 11 12 13 14)
; intersection
(print (intersect set1 set2))
; ==> (3 4 5)
; difference
(print (diff set1 set2))
; ==> (1 2 6 7 8 9)
; subset (no predefined function)
(define (subset? a b)
(all (lambda (i) (has? b i)) a))
(print (subset? set3 set1))
; ==> #true
(print (subset? set3 set2))
; ==> #false
; equality
(print (equal? set1 set2))
; ==> #false
(print (equal? set1 set4))
; ==> #true
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#ERRE
|
ERRE
|
PROGRAM SIEVE_ORG
! --------------------------------------------------
! Eratosthenes Sieve Prime Number Program in BASIC
! (da 3 a SIZE*2) from Byte September 1981
!---------------------------------------------------
CONST SIZE%=8190
DIM FLAGS%[SIZE%]
BEGIN
PRINT("Only 1 iteration")
COUNT%=0
FOR I%=0 TO SIZE% DO
IF FLAGS%[I%]=TRUE THEN
!$NULL
ELSE
PRIME%=I%+I%+3
K%=I%+PRIME%
WHILE NOT (K%>SIZE%) DO
FLAGS%[K%]=TRUE
K%=K%+PRIME%
END WHILE
PRINT(PRIME%;)
COUNT%=COUNT%+1
END IF
END FOR
PRINT
PRINT(COUNT%;" PRIMES")
END PROGRAM
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Transd
|
Transd
|
#lang transd
MainModule: {
_start: (λ (with fs FileStream()
(open-r fs "/mnt/vault/tmp/unixdict.txt") )
(with v ( -|
(read-text fs)
(split)
(group-by (λ s String() -> String()
(ret (min s (reverse (cp s))))))
(values)
(filter where: (λ v Vector<String>() (ret (== (size v) 2))))
(shuffle))
(lout "Total number of semordnilaps: " (size v))
(lout "Random five: " Range(in: v 0 5))))
)
}
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#TUSCRIPT
|
TUSCRIPT
|
$$ MODE TUSCRIPT,{}
requestdata = REQUEST ("http://www.puzzlers.org/pub/wordlists/unixdict.txt")
DICT semordnilap CREATE 99999
COMPILE
LOOP r=requestdata
rstrings=STRINGS(r," ? ")
rreverse=REVERSE(rstrings)
revstring=EXCHANGE (rreverse,":'':':'::")
group=APPEND (r,revstring)
sort=ALPHA_SORT (group)
DICT semordnilap APPEND/QUIET/COUNT sort,num,cnt,"",""
ENDLOOP
DICT semordnilap UNLOAD wordgroups,num,howmany
get_palins=FILTER_INDEX (howmany,-," 1 ")
size=SIZE(get_palins)
PRINT "unixdict.txt contains ", size, " palindromes"
PRINT " "
palindromes=SELECT (wordgroups,#get_palins)
LOOP n=1,5
take5=SELECT (palindromes,#n)
PRINT n,". ",take5
ENDLOOP
ENDCOMPILE
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#PL.2FI
|
PL/I
|
/* Compute SEDOLs; includes check for invalid characters. */
sedol: procedure options (main); /* 3 March 2012 */
declare alphabet character (36) static initial
('0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ');
declare weight (6) fixed static initial (1, 3, 1, 7, 3, 9);
declare s character (6);
declare (i, v, k) fixed;
do while ('1'b);
get edit (s) (a(6));
put skip edit (s) (a);
/* Check for invalid characters: */
if verify(s, '0123456789BCDFGHJKLMNPQRSTVWXYZ') > 0 then stop;
v = 0;
do i = 1 to 6;
k = index(alphabet, substr(s, i, 1)) - 1;
v = v + weight(i) * k;
end;
k = mod(v, 10);
v = mod(10 - k, 10);
put edit (s, v) (x(2), a, f(1)); put edit (' ') (a);
end;
end sedol;
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Ring
|
Ring
|
for n=1 to 22
x = n + floor(1/2 + sqrt(n))
see "" + x + " "
next
see nl
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Ruby
|
Ruby
|
def f(n)
n + (0.5 + Math.sqrt(n)).floor
end
(1..22).each { |n| puts "#{n} #{f(n)}" }
non_squares = (1..1_000_000).map { |n| f(n) }
squares = (1..1001).map { |n| n**2 } # Note: 1001*1001 = 1_002_001 > 1_001_000 = f(1_000_000)
(squares & non_squares).each do |n|
puts "Oops, found a square f(#{non_squares.index(n)}) = #{n}"
end
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#ooRexx
|
ooRexx
|
-- Set creation
-- Using the OF method
s1 = .set~of(1, 2, 3, 4, 5, 6)
-- Explicit addition of individual items
s2 = .set~new
s2~put(2)
s2~put(4)
s2~put(6)
-- group addition
s3 = .set~new
s3~putall(.array~of(1, 3, 5))
-- Test m ? S -- "m is an element in set S"
say s1~hasindex(1) s3~hasindex(2) -- "1 0", which is "true" and "false"
-- A ? B -- union; a set of all elements either in set A or in set B.
s4 = s2~union(s3) -- {1, 2, 3, 4, 5, 6}
Call show 's4',s4
-- A ? B -- intersection; a set of all elements in both set A and set B.
s5 = s1~intersection(s2) -- {2, 4, 6}
Call show 's5',s5
-- A ? B -- difference; a set of all elements in set A, except those in set B.
s6 = s1~difference(s2) -- {1, 3, 5}
Call show 's6',s6
-- A ? B -- subset; true if every element in set A is also in set B.
say s1~subset(s2) s2~subset(s1) -- "0 1"
-- A = B -- equality; true if every element of set A is in set B and vice-versa.
-- No direct equivalence method, but the XOR method can be used to determine this
say s1~xor(s4)~isempty -- true
Exit
show: Procedure
Use Arg set_name,set
Say set_name':' set~makearray~makestring((LINE),',')
return
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Euphoria
|
Euphoria
|
constant limit = 1000
sequence flags,primes
flags = repeat(1, limit)
for i = 2 to sqrt(limit) do
if flags[i] then
for k = i*i to limit by i do
flags[k] = 0
end for
end if
end for
primes = {}
for i = 2 to limit do
if flags[i] = 1 then
primes &= i
end if
end for
? primes
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#VBScript
|
VBScript
|
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set objInFile = objFSO.OpenTextFile(objFSO.GetParentFolderName(WScript.ScriptFullName) &_
"\unixdict.txt",1)
Set objUnixDict = CreateObject("Scripting.Dictionary")
Set objSemordnilap = CreateObject("Scripting.Dictionary")
Do Until objInFile.AtEndOfStream
line = objInFile.ReadLine
If Len(line) > 1 Then
objUnixDict.Add line,""
End If
reverse_line = StrReverse(line)
If reverse_line <> line And objUnixDict.Exists(reverse_line) Then
objSemordnilap.Add line, reverse_line
End If
Loop
'Display the first 5 keys.
k = 0
For Each Key In objSemordnilap.Keys
WScript.StdOut.Write Key & " - " & objSemordnilap.Item(Key)
WScript.StdOut.WriteLine
k = k + 1
If k = 5 Then
Exit For
End If
Next
WScript.StdOut.Write "Total Count: " & objSemordnilap.Count
WScript.StdOut.WriteLine
objInFile.Close
Set objFSO = Nothing
Set objUnixDict = Nothing
Set objSemordnilap = Nothing
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#Wren
|
Wren
|
import "io" for File
var dict = File.read("unixdict.txt").split("\n")
var wmap = {}
dict.each { |w| wmap[w] = true }
var pairs = []
var used = {}
for (word in dict) {
if (word != "") {
var pal = word[-1..0]
if (word != pal && wmap[pal] && !used[pal]) {
pairs.add([word, pal])
used[word] = true
}
}
}
System.print("There are %(pairs.count) unique semordnilap pairs in the dictionary.")
System.print("\nIn sorted order, the first five are:")
for (i in 0..4) System.print(" %(pairs[i][0]), %(pairs[i][1])")
System.print("\nand the last five are:")
for (i in -5..-1) System.print(" %(pairs[i][0]), %(pairs[i][1])")
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Potion
|
Potion
|
sedolnum = (c) :
if ("0" ord <= c ord and c ord <= "9" ord): c number integer.
else: 10 + c ord - "A" ord.
.
sedol = (str) :
weight = (1, 3, 1, 7, 3, 9)
sum = 0
6 times (i) :
sum = sum + sedolnum(str(i)) * weight(i)
.
(str, (10 - (sum % 10)) % 10) join
.
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#PowerShell
|
PowerShell
|
function Add-SEDOLCheckDigit
{
Param ( # Validate input as six-digit SEDOL number
[ValidatePattern( "^[0123456789bcdfghjklmnpqrstvwxyz]{6}$" )]
[parameter ( Mandatory = $True ) ]
[string]
$SixDigitSEDOL )
# Convert to array of single character strings, using type char as an intermediary
$SEDOL = [string[]][char[]]$SixDigitSEDOL
# Define place weights
$Weight = @( 1, 3, 1, 7, 3, 9 )
# Define character values (implicit in 0-based location within string)
$Characters = "0123456789abcdefghijklmnopqrstuvwxyz"
$CheckSum = 0
# For each digit, multiply the character value by the weight and add to check sum
0..5 | ForEach { $CheckSum += $Characters.IndexOf( $SEDOL[$_].ToLower() ) * $Weight[$_] }
# Derive the check digit from the partial check sum
$CheckDigit = ( 10 - $CheckSum % 10 ) % 10
# Return concatenated result
return ( $SixDigitSEDOL + $CheckDigit )
}
# Test
$List = @(
"710889"
"B0YBKJ"
"406566"
"B0YBLH"
"228276"
"B0YBKL"
"557910"
"B0YBKR"
"585284"
"B0YBKT"
"B00030"
)
ForEach ( $PartialSEDOL in $List )
{
Add-SEDOLCheckDigit -SixDigitSEDOL $PartialSEDOL
}
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Rust
|
Rust
|
fn f(n: i64) -> i64 {
n + (0.5 + (n as f64).sqrt()) as i64
}
fn is_sqr(n: i64) -> bool {
let a = (n as f64).sqrt() as i64;
n == a * a || n == (a+1) * (a+1) || n == (a-1) * (a-1)
}
fn main() {
println!( "{:?}", (1..23).map(|n| f(n)).collect::<Vec<i64>>() );
let count = (1..1_000_000).map(|n| f(n)).filter(|&n| is_sqr(n)).count();
println!("{} unexpected squares found", count);
}
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Scala
|
Scala
|
def nonsqr(n:Int)=n+math.round(math.sqrt(n)).toInt
for(n<-1 to 22) println(n + " "+ nonsqr(n))
val test=(1 to 1000000).exists{n =>
val j=math.sqrt(nonsqr(n))
j==math.floor(j)
}
println("squares up to one million="+test)
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#PARI.2FGP
|
PARI/GP
|
setsubset(s,t)={
for(i=1,#s,
if(!setsearch(t,s[i]), return(0))
);
1
};
s=Set([1,2,2])
t=Set([4,2,4])
setsearch(s,1)
setunion(s,t)
setintersect(s,t)
setminus(s,t)
setsubset(s,t)
s==t
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#F.23
|
F#
|
let primes max =
let mutable xs = [|2..max|]
let limit = max |> float |> sqrt |> int
for x in [|2..limit|] do
xs <- xs |> Array.except [|x*x..x..max|]
xs
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#XPL0
|
XPL0
|
include c:\cxpl\codes; \intrinsic 'code' declarations
string 0; \use zero-terminated strings
def LF=$0A, CR=$0D, EOF=$1A;
proc RevStr(S); \Reverse order of characters in a string
char S;
int I, J, T;
[J:= 0;
while S(J) do J:= J+1;
J:= J-1;
I:= 0;
while I<J do
[T:= S(I); S(I):= S(J); S(J):= T; \swap
I:= I+1; J:= J-1;
];
];
func StrEqual(S1, S2); \Compare strings, return 'true' if equal
char S1, S2;
int I;
[for I:= 0 to 80-1 do
[if S1(I) # S2(I) then return false;
if S1(I) = 0 then return true;
];
];
int C, I, J, SJ, Count;
char Dict, Word(80);
[\Read file on command line redirected as input, i.e: <unixdict.txt
Dict:= GetHp; \starting address of block of local "heap" memory
I:= 0; \ [GetHp does exact same thing as Reserve(0)]
repeat repeat C:= ChIn(1) until C#LF; \get chars sans line feeds
if C = CR then C:= 0; \replace carriage return with terminator
Dict(I):= C; I:= I+1;
until C = EOF;
SetHp(Dict+I); \set heap pointer beyond Dict
I:= 0; Count:= 0;
loop [J:= 0; \get word at I
repeat C:= Dict(I+J); Word(J):= C; J:= J+1;
until C=0;
RevStr(Word);
J:= J+I; \set J to following word in Dict
if Dict(J) = EOF then quit;
SJ:= J; \save index to following word
loop [if StrEqual(Word, Dict+J) then
[Count:= Count+1;
if Count <= 5 then
[RevStr(Word); \show some examples
Text(0, Word); ChOut(0, ^ ); Text(0, Dict+J); CrLf(0);
];
quit;
];
repeat J:= J+1 until Dict(J) = 0;
J:= J+1;
if Dict(J) = EOF then quit;
];
I:= SJ; \next word
];
IntOut(0, Count); CrLf(0);
]
|
http://rosettacode.org/wiki/Semordnilap
|
Semordnilap
|
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap pairs, and print 5 examples.
Two matching semordnilaps, such as lager and regal, should be counted as one unique pair.
(Note that the word "semordnilap" is not in the above dictionary.)
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
|
#zkl
|
zkl
|
var [const] words= // create hashed unixdict of striped words (word:True, ...)
File("dict.txt").howza(11).pump(Dictionary().howza(8).add.fp1(True));
ss:=words.pump(List, // push stripped unixdict words through some functions
fcn(w){ words.holds(w.reverse()) }, Void.Filter, // filter palindromes
// create ("word","drow") if "word"<"drow" (ie remove duplicates)
fcn(w){ r:=w.reverse(); if(w<r) T(w,r) else Void.Skip });
ss.len().println(); //--> 158
ss.shuffle()[0,5].println();
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#PureBasic
|
PureBasic
|
Procedure.s SEDOLs(rawstring$)
Protected i, j, sum, c, m
For i=1 To Len(rawstring$)
c=Asc(Mid(rawstring$,i,1))
Select c
Case Asc("0") To Asc("9")
j=Val(Mid(rawstring$,i,1))
Default
j=c-Asc("A")
EndSelect
Select i
Case 1, 3, 7: m=1
Case 2, 5: m=3
Case 4: m=7
Default: m=9
EndSelect
sum+j*m
Next
sum=(10-(sum%10))%10
ProcedureReturn rawstring$+Str(sum)
EndProcedure
Define result$, i
Restore Tests
For i=0 To 10
Read.s SEDOL$
result$+SEDOLs(SEDOL$)
If i%2
result$+#CRLF$
ElseIf i<10
result$+", "
EndIf
Next
MessageRequester("SEDOLs","Result"+#CRLF$+result$)
DataSection
Tests:
Data.s "710889","B0YBKJ","406566","B0YBLH","228276"
Data.s "B0YBKL","557910","B0YBKR","585284","B0YBKT","B00030"
EndDataSection
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Scheme
|
Scheme
|
(define non-squares
(lambda (index)
(+ index (inexact->exact (floor (+ (/ 1 2) (sqrt index)))))))
(define sequence
(lambda (function)
(lambda (start)
(lambda (stop)
(if (> start stop)
(list)
(cons (function start)
(((sequence function) (+ start 1)) stop)))))))
(define square?
(lambda (number)
((lambda (root)
(= (* root root) number))
(floor (sqrt number)))))
(define any?
(lambda (predicate?)
(lambda (list)
(and (not (null? list))
(or (predicate? (car list))
((any? predicate?) (cdr list)))))))
(display (((sequence non-squares) 1) 22))
(newline)
(display ((any? square?) (((sequence non-squares) 1) 999999)))
(newline)
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Pascal
|
Pascal
|
program Rosetta_Set;
{$mode objfpc}{$H+}
uses {$IFDEF UNIX} {$IFDEF UseCThreads}
cthreads, {$ENDIF} {$ENDIF}
Classes;
{$R *.res}
type
CharSet = set of char;
var
A, B, C, S: CharSet;
M: char;
function SetToString(const ASet: CharSet): string;
var
J: char;
begin
Result := '';
// Test all chars
for J in char do
// If the char is in set, add to result
if J in ASet then
Result := Result + J + ', ';
// Clear the result
if Result > '' then
Delete(Result, Length(Result) - 1, 2);
end;
procedure PrintSet(const ASet: CharSet; const ASetName: string;
const ATitle: string = '');
begin
if ATitle > '' then
WriteLn(ATitle);
WriteLn(ASetName, ' = [', SetToString(ASet), ']', #10);
end;
procedure ShowEqual(const ASetA, ASetB: CharSet; const ASetNameA, ASetNameB: string);
begin
WriteLn(ASetNameA, ' = [', SetToString(ASetA), ']');
WriteLn(ASetNameB, ' = [', SetToString(ASetB), ']');
if ASetA = ASetB then
WriteLn(ASetNameA, ' = ', ASetNameB)
else
WriteLn(ASetNameA, ' <> ', ASetNameB);
end;
begin
// Set Creation
A := ['A', 'B', 'C', 'D', 'E', 'F'];
B := ['E', 'F', 'G', 'H', 'I', 'J'];
PrintSet(A, 'A', 'Set Creation');
PrintSet(B, 'B');
// Test m ∈ S -- "m is an element in set S"
M := 'A';
if M in A then
WriteLn('"A" is in set A');
// A ∪ B -- union; a set of all elements either in set A or in set B.
S := A + B;
PrintSet(S, 'S', 'S = A U B -- union; a set of all elements either in set A or in set B.');
// A ∩ B -- intersection; a set of all elements in both set A and set B.
S := A * B;
PrintSet(S, 'S',
'S = A ∩ B -- intersection; a set of all elements in both set A and set B.');
// A \ B -- difference; a set of all elements in set A, except those in set B.
S := A - B;
PrintSet(S, 'S',
'S = A \ B -- difference; a set of all elements in set A, except those in set B.');
// A ⊆ B -- subset; true if every element in set A is also in set B.
Writeln('A ⊆ B -- subset; true if every element in set A is also in set B.');
if A <= B then
WriteLn('A in B')
else
Writeln('A is not in B');
Writeln;
//A = B -- equality; true if every element of set A is in set B and vice-versa.
Writeln('A = B -- equality; true if every element of set A is in set B and vice-versa.');
ShowEqual(A, B, 'A', 'B');
S := A * B;
C := ['E', 'F'];
ShowEqual(S, C, 'S', 'C');
readln;
end.
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Factor
|
Factor
|
USING: bit-arrays io kernel locals math math.functions
math.ranges prettyprint sequences ;
IN: rosetta-code.sieve-of-erato
<PRIVATE
: init-sieve ( n -- seq ) ! Include 0 and 1 for easy indexing.
1 - <bit-array> dup set-bits ?{ f f } prepend ;
! Given the sieve and a prime starting index, create a range of
! values to mark composite. Start at the square of the prime.
: to-mark ( seq n -- range )
[ length 1 - ] [ dup dup * ] bi* -rot <range> ;
! Mark multiples of prime n as composite.
: mark-nths ( seq n -- )
dupd to-mark [ swap [ f ] 2dip set-nth ] with each ;
: next-prime ( index seq -- n ) [ t = ] find-from drop ;
PRIVATE>
:: sieve ( n -- seq )
n sqrt 2 n init-sieve :> ( limit i! s )
[ i limit < ] ! sqrt optimization
[ s i mark-nths i 1 + s next-prime i! ] while t s indices ;
: sieve-demo ( -- )
"Primes up to 120 using sieve of Eratosthenes:" print
120 sieve . ;
MAIN: sieve-demo
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Python
|
Python
|
def char2value(c):
assert c not in 'AEIOU', "No vowels"
return int(c, 36)
sedolweight = [1,3,1,7,3,9]
def checksum(sedol):
tmp = sum(map(lambda ch, weight: char2value(ch) * weight,
sedol, sedolweight)
)
return str((10 - (tmp % 10)) % 10)
for sedol in '''
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
'''.split():
print sedol + checksum(sedol)
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Seed7
|
Seed7
|
$ include "seed7_05.s7i";
include "float.s7i";
include "math.s7i";
const func integer: nonsqr (in integer: n) is
return n + trunc(0.5 + sqrt(flt(n)));
const proc: main is func
local
var integer: i is 0;
var float: j is 0.0;
begin
# First 22 values (as a list) has no squares:
for i range 1 to 22 do
write(nonsqr(i) <& " ");
end for;
writeln;
# The following check shows no squares up to one million:
for i range 1 to 1000000 do
j := sqrt(flt(nonsqr(i)));
if j = floor(j) then
writeln("Found square for nonsqr(" <& i <& ")");
end if;
end for;
end func;
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Sidef
|
Sidef
|
func nonsqr(n) { 0.5 + n.sqrt -> floor + n }
{|i| nonsqr(i) }.map(1..22).join(' ').say
{ |i|
if (nonsqr(i).is_sqr) {
die "Found a square in the sequence: #{i}"
}
} << 1..1e6
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Perl
|
Perl
|
use strict;
package Set; # likely will conflict with stuff on CPAN
use overload
'""' => \&str,
'bool' => \&count,
'+=' => \&add,
'-=' => \&del,
'-' => \&diff,
'==' => \&eq,
'&' => \&intersection,
'|' => \&union,
'^' => \&xdiff;
sub str {
my $set = shift;
# This has drawbacks: stringification is used as set key
# if the set is added to another set as an element, which
# may cause inconsistencies if the element set is modified
# later. In general, a hash key loses its object identity
# anyway, so it's not unique to us.
"Set{ ". join(", " => sort map("$_", values %$set)) . " }"
}
sub new {
my $pkg = shift;
my $h = bless {};
$h->add($_) for @_;
$h
}
sub add {
my ($set, $elem) = @_;
$set->{$elem} = $elem;
$set
}
sub del {
my ($set, $elem) = @_;
delete $set->{$elem};
$set
}
sub has { # set has element
my ($set, $elem) = @_;
exists $set->{$elem}
}
sub union {
my ($this, $that) = @_;
bless { %$this, %$that }
}
sub intersection {
my ($this, $that) = @_;
my $s = new Set;
for (keys %$this) {
$s->{$_} = $this->{$_} if exists $that->{$_}
}
$s
}
sub diff {
my ($this, $that) = @_;
my $s = Set->new;
for (keys %$this) {
$s += $this->{$_} unless exists $that->{$_}
}
$s
}
sub xdiff { # xor, symmetric diff
my ($this, $that) = @_;
my $s = new Set;
bless { %{ ($this - $that) | ($that - $this) } }
}
sub count { scalar(keys %{+shift}) }
sub eq {
my ($this, $that) = @_;
!($this - $that) && !($that - $this);
}
sub contains { # this is a superset of that
my ($this, $that) = @_;
for (keys %$that) {
return 0 unless $this->has($_)
}
return 1
}
package main;
my ($x, $y, $z, $w);
$x = Set->new(1, 2, 3);
$x += $_ for (5 .. 7);
$y = Set->new(1, 2, 4, $x); # not the brightest idea
print "set x is: $x\nset y is: $y\n";
for (1 .. 4, $x) {
print "$_ is", $y->has($_) ? "" : " not", " in y\n";
}
print "union: ", $x | $y, "\n";
print "intersect: ", $x & $y, "\n";
print "z = x - y = ", $z = $x - $y, "\n";
print "y is ", $x->contains($y) ? "" : "not ", "a subset of x\n";
print "z is ", $x->contains($z) ? "" : "not ", "a subset of x\n";
print "z = (x | y) - (x & y) = ", $z = ($x | $y) - ($x & $y), "\n";
print "w = x ^ y = ", $w = ($x ^ $y), "\n";
print "w is ", ($w == $z) ? "" : "not ", "equal to z\n";
print "w is ", ($w == $x) ? "" : "not ", "equal to x\n";
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#FOCAL
|
FOCAL
|
1.1 T "PLEASE ENTER LIMIT"
1.2 A N
1.3 I (2047-N)5.1
1.4 D 2
1.5 Q
2.1 F X=2,FSQT(N); D 3
2.2 F W=2,N; I (SIEVE(W)-2)4.1
3.1 I (-SIEVE(X))3.3
3.2 F Y=X*X,X,N; S SIEVE(Y)=2
3.3 R
4.1 T %4.0,W,!
5.1 T "PLEASE ENTER A NUMBER LESS THAN 2048."!; G 1.1
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Q
|
Q
|
scd:{
v:{("i"$x) - ?[("0"<=x) & x<="9"; "i"$"0"; -10+"i"$"A"]} each x; / Turn characters of SEDOL into their values
w:sum v*1 3 1 7 3 9; / Weighted sum of values
d:(10 - w mod 10) mod 10; / Check digit value
x,"c"$(("i"$"0")+d) / Append to SEDOL
}
scd each ("710889";"B0YBKJ";"406566";"B0YBLH";"228276";"B0YBKL";"557910";"B0YBKR";"585284";"B0YBKT";"B00030")
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Smalltalk
|
Smalltalk
|
| nonSquare isSquare squaresFound |
nonSquare := [:n |
n + (n sqrt) rounded
].
isSquare := [:n |
n = (((n sqrt) asInteger) raisedTo: 2)
].
Transcript show: 'The first few non-squares:'; cr.
1 to: 22 do: [:n |
Transcript show: (nonSquare value: n) asString; cr
].
squaresFound := 0.
1 to: 1000000 do: [:n |
(isSquare value: (nonSquare value: n)) ifTrue: [
squaresFound := squaresFound + 1
]
].
Transcript show: 'Squares found for values up to 1,000,000: ';
show: squaresFound asString; cr
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Standard_ML
|
Standard ML
|
- fun nonsqr n = n + round (Math.sqrt (real n));
val nonsqr = fn : int -> int
- List.tabulate (23, nonsqr);
val it = [0,2,3,5,6,7,8,10,11,12,13,14,...] : int list
- let fun loop i = if i = 1000000 then true
else let val j = Math.sqrt (real (nonsqr i)) in
Real.!= (j, Real.realFloor j) andalso
loop (i+1)
end in
loop 1
end;
val it = true : bool
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Phix
|
Phix
|
with javascript_semantics
function is_element(object x, sequence set)
return find(x,set)!=0
end function
function set_union(sequence set1, set2)
for i=1 to length(set2) do
if not is_element(set2[i],set1) then
set1 = append(set1,set2[i])
end if
end for
return set1
end function
function set_intersection(sequence set1, set2)
sequence res = {}
for i=1 to length(set1) do
if is_element(set1[i],set2) then
res = append(res,set1[i])
end if
end for
return res
end function
function set_difference(sequence set1, set2)
sequence res = {}
for i=1 to length(set1) do
if not is_element(set1[i],set2) then
res = append(res,set1[i])
end if
end for
return res
end function
function set_subset(sequence set1, set2)
for i=1 to length(set1) do
if not is_element(set1[i],set2) then
return false
end if
end for
return true
end function
function set_equality(sequence set1, set2)
if length(set1)!=length(set2) then
return false
end if
return set_subset(set1,set2)
end function
--test code:
?is_element(3,{1,2,3}) -- 1
?is_element(4,{1,2,3}) -- 0
?set_union({1,2,3},{3,4,5}) -- {1,2,3,4,5}
?set_intersection({1,2,3},{3,4,5}) -- {3}
?set_difference({1,2,3},{3,4,5}) -- {1,2}
?set_subset({1,2,3},{3,4,5}) -- 0
?set_subset({1,2},{1,2,3}) -- 1
?set_equality({1,2,3},{3,4,5}) -- 0
?set_equality({1,2,3},{3,1,2}) -- 1
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Forth
|
Forth
|
: prime? ( n -- ? ) here + c@ 0= ;
: composite! ( n -- ) here + 1 swap c! ;
: sieve ( n -- )
here over erase
2
begin
2dup dup * >
while
dup prime? if
2dup dup * do
i composite!
dup +loop
then
1+
repeat
drop
." Primes: " 2 do i prime? if i . then loop ;
100 sieve
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#R
|
R
|
# Read in data from text connection
datalines <- readLines(tc <- textConnection("710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT")); close(tc)
# Check data valid
checkSedol <- function(datalines)
{
ok <- grep("^[[:digit:][:upper:]]{6}$", datalines)
if(length(ok) < length(datalines))
{
stop("there are invalid lines")
}
}
checkSedol(datalines)
# Append check digit
appendCheckDigit <- function(x)
{
if(length(x) > 1) return(sapply(x, appendCheckDigit))
ascii <- as.integer(charToRaw(x))
scores <- ifelse(ascii < 65, ascii - 48, ascii - 55)
weights <- c(1, 3, 1, 7, 3, 9)
chkdig <- (10 - sum(scores * weights) %% 10) %% 10
paste(x, as.character(chkdig), sep="")
}
withchkdig <- appendCheckDigit(datalines)
#Print in format requested
writeLines(withchkdig)
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Tcl
|
Tcl
|
package require Tcl 8.5
set f {n {expr {$n + floor(0.5 + sqrt($n))}}}
for {set x 1} {$x <= 22} {incr x} {
puts [format "%d\t%s" $x [apply $f $x]]
}
puts "looking for a square..."
for {set x 1} {$x <= 1000000} {incr x} {
set y [apply $f $x]
set s [expr {sqrt($y)}]
if {$s == int($s)} {
error "found a square in the sequence: $x -> $y"
}
}
puts "done"
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#TI-89_BASIC
|
TI-89 BASIC
|
■ n+floor(1/2+√(n)) → f(n)
Done
■ seq(f(n),n,1,22)
{2,3,5,6,7,8,10,11,12,13,14,15,17,18,19,20,21,22,23,24,26,27}
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#PicoLisp
|
PicoLisp
|
(setq
Set1 (1 2 3 7 abc "def" (u v w))
Set2 (2 3 5 hello (x y z))
Set3 (3 hello (x y z)) )
# Element tests (any non-NIL value means "yes")
: (member "def" Set1)
-> ("def" (u v w))
: (member "def" Set2)
-> NIL
: (member '(x y z) Set2)
-> ((x y z))
# Union
: (uniq (append Set1 Set2))
-> (1 2 3 7 abc "def" (u v w) 5 hello (x y z))
# Intersection
: (sect Set1 Set2)
-> (2 3)
# Difference
: (diff Set1 Set2)
-> (1 7 abc "def" (u v w))
# Test for subset
: (not (diff Set1 Set2))
-> NIL # Set1 is not a subset of Set2
: (not (diff Set3 Set2))
-> T # Set3 is a subset of Set2
# Test for equality
: (= (sort (copy Set1)) (sort (copy Set2)))
-> NIL
: (= (sort (copy Set2)) (sort (copy Set2)))
-> T
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Fortran
|
Fortran
|
program sieve
implicit none
integer, parameter :: i_max = 100
integer :: i
logical, dimension (i_max) :: is_prime
is_prime = .true.
is_prime (1) = .false.
do i = 2, int (sqrt (real (i_max)))
if (is_prime (i)) is_prime (i * i : i_max : i) = .false.
end do
do i = 1, i_max
if (is_prime (i)) write (*, '(i0, 1x)', advance = 'no') i
end do
write (*, *)
end program sieve
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Racket
|
Racket
|
#lang racket
;;; Since the Task gives us unchecksummed and checksummed SEDOLs, and
;;; we'll just take a list of the output SEDOLs and remove their last
;;; characters for the input
(define output-SEDOLS
(list "7108899" "B0YBKJ7" "4065663"
"B0YBLH2" "2282765" "B0YBKL9"
"5579107" "B0YBKR5" "5852842"
"B0YBKT7" "B000300"))
(define (output->input-SEDOL S) (substring S 0 6))
(define input-SEDOLS (map output->input-SEDOL output-SEDOLS))
;;; checksum calculation
(define (SEDOL-character-value c)
(if (char-numeric? c)
(- (char->integer c) (char->integer #\0))
(+ 10 (- (char->integer c) (char->integer #\A)))))
(define (SEDOL-character-sum S)
(for/sum ((c S) ; if we run out of c's before the final 1 in weight, we'll have the unchecksummed weighted sum
(weight (in-list '(1 3 1 7 3 9 1))))
(* weight (SEDOL-character-value c))))
(define (SEDOL-checksum S) (number->string (modulo (- 10 (SEDOL-character-sum S)) 10)))
;;; build output from input
(define (SEDOL-append-checksum S) (string-append S (SEDOL-checksum S)))
;;; Extra credit -- according to wikipedia:
;;; "SEDOLs are seven characters in length"
;;; "vowels are never used"
;;; there seems to be no statement as to case, but we'll assert that too!
;;;
;;; valid-SEDOL? is a predicate... it doesn't report a reason
(define (invalid-SEDOL? S)
(define (invalid-SEDOL-character? c)
(if
(and (not (char-upper-case? c)) (not (char-numeric? c)))
(format "contains non upper case/non numeric ~a" c)
(case c [(#\A #\E #\I #\O #\U) (format "contains vowel ~a" c)] [else #f])))
(cond
[(< (string-length S) 7) "too few characters"]
[(> (string-length S) 7) "too many characters"]
[(not (zero? (modulo (SEDOL-character-sum S) 10))) "invalid checksum"]
[(for/first ((c S) #:when (invalid-SEDOL-character? c)) c) => identity]
[else #f])) ; a.k.a. valid!
(module+ main
(for* ((S input-SEDOLS))
(displayln (SEDOL-append-checksum S)))
(newline)
(displayln "Extra Credit!")
(displayln (invalid-SEDOL? "B0YBKT7")) ; expect #f output
(displayln (invalid-SEDOL? "B000301")) ; expect "invalid checksum" output
)
(module+ test
(require rackunit)
(check-= (SEDOL-character-value #\3) 3 0)
(check-= (SEDOL-character-value #\B) 11 0)
(check-equal? (invalid-SEDOL? "B000301") "invalid checksum")
(for ((S output-SEDOLS))
(check-false (invalid-SEDOL? S))
(check-equal? (SEDOL-append-checksum (substring S 0 6))
S (format "test SEDOL for ~a" S))))
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Raku
|
Raku
|
sub sedol( Str $s ) {
die 'No vowels allowed' if $s ~~ /<[AEIOU]>/;
die 'Invalid format' if $s !~~ /^ <[0..9B..DF..HJ..NP..TV..Z]>**6 $ /;
my %base36 = (flat 0..9, 'A'..'Z') »=>« ^36;
my @weights = 1, 3, 1, 7, 3, 9;
my @vs = %base36{ $s.comb };
my $checksum = [+] @vs Z* @weights;
my $check_digit = (10 - $checksum % 10) % 10;
return $s ~ $check_digit;
}
say sedol($_) for <
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
>;
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Transd
|
Transd
|
#lang transd
MainModule: {
nonsqr: (λ i Int()
(ret (+ i (to-Int (floor (+ 0.5 (sqrt i))))))),
_start: (lambda locals: d Double()
(for i in Range(1 23) do
(textout (nonsqr i) " "))
(for i in Range(1 1000001) do
(= d (sqrt (nonsqr i)))
(if (eq d (floor d))
(throw String("Square: " i))))
(textout "\n\nUp to 1 000 000 - no squares found.")
)
}
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#True_BASIC
|
True BASIC
|
FUNCTION nonSquare (n)
LET nonSquare = n + INT(0.5 + SQR(n))
END FUNCTION
! Display first 22 values
PRINT "The first 22 numbers generated by the sequence are : "
FOR i = 1 TO 22
PRINT nonSquare(i); " ";
NEXT i
PRINT
! Check FOR squares up TO one million
LET found = 0
FOR i = 1 TO 1e6
LET j = SQR(nonSquare(i))
IF j = INT(j) THEN
LET found = 1
PRINT i, " square numbers found"
EXIT FOR
END IF
NEXT i
IF found = 0 THEN PRINT "No squares found"
END
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#PowerShell
|
PowerShell
|
[System.Collections.Generic.HashSet[object]]$set1 = 1..4
[System.Collections.Generic.HashSet[object]]$set2 = 3..6
# Operation + Definition + Result
#--------------------------------+---------------------+-------------------------
$set1.UnionWith($set2) # Union $set1 = 1, 2, 3, 4, 5, 6
$set1.IntersectWith($set2) # Intersection $set1 = 3, 4
$set1.ExceptWith($set2) # Difference $set1 = 1, 2
$set1.SymmetricExceptWith($set2) # Symmetric difference $set1 = 1, 2, 6, 5
$set1.IsSupersetOf($set2) # Test superset False
$set1.IsSubsetOf($set2) # Test subset False
$set1.Equals($set2) # Test equality False
$set1.IsProperSupersetOf($set2) # Test proper superset False
$set1.IsProperSubsetOf($set2) # Test proper subset False
5 -in $set1 # Test membership False
7 -notin $set1 # Test non-membership True
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Free_Pascal
|
Free Pascal
|
program prime_sieve;
{$mode objfpc}{$coperators on}
uses
SysUtils, GVector;
type
TPrimeList = specialize TVector<DWord>;
function Sieve(aLimit: DWord): TPrimeList;
var
IsPrime: array of Boolean;
I, SqrtBound: DWord;
J: QWord;
begin
Result := TPrimeList.Create;
Inc(aLimit, Ord(aLimit < High(DWord))); //not a problem because High(DWord) is composite
SetLength(IsPrime, aLimit);
FillChar(Pointer(IsPrime)^, aLimit, Byte(True));
SqrtBound := Trunc(Sqrt(aLimit));
for I := 2 to aLimit do
if IsPrime[I] then
begin
Result.PushBack(I);
if I <= SqrtBound then
begin
J := I * I;
repeat
IsPrime[J] := False;
J += I;
until J > aLimit;
end;
end;
end;
//usage
var
Limit: DWord = 0;
function ReadLimit: Boolean;
var
Lim: Int64;
begin
if (ParamCount = 1) and Lim.TryParse(ParamStr(1), Lim) then
if (Lim >= 0) and (Lim <= High(DWord)) then
begin
Limit := DWord(Lim);
exit(True);
end;
Result := False;
end;
procedure PrintUsage;
begin
WriteLn('Usage: prime_sieve Limit');
WriteLn(' where Limit in the range [0, ', High(DWord), ']');
Halt;
end;
procedure PrintPrimes(aList: TPrimeList);
var
I: DWord;
begin
for I := 0 to aList.Size - 2 do
Write(aList[I], ', ');
WriteLn(aList[aList.Size - 1]);
aList.Free;
end;
begin
if not ReadLimit then
PrintUsage;
try
PrintPrimes(Sieve(Limit));
except
on e: Exception do
WriteLn('An exception ', e.ClassName, ' occurred with message: ', e.Message);
end;
end.
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#REXX
|
REXX
|
╔════════════════════════════════════════════════════════════════════╗
║ If the SEDOL is 6 characters, a check digit is added. ║
║ ║
║ If the SEDOL is 7 characters, a check digit is created and it's ║
║ verified that it's equal to the check digit already on the SEDOL. ║
╚════════════════════════════════════════════════════════════════════╝
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Ring
|
Ring
|
see sedol("710889") + nl
see sedol("B0YBKJ") + nl
see sedol("406566") + nl
see sedol("B0YBLH") + nl
see sedol("228276") + nl
see sedol("B0YBKL") + nl
see sedol("557910") + nl
see sedol("B0YBKR") + nl
see sedol("585284") + nl
see sedol("B0YBKT") + nl
see sedol("B00030") + nl
func sedol d
d = upper(d)
s = 0
weights = [1, 3, 1, 7, 3, 9]
for i = 1 to 6
a = substr(d,i,1)
if ascii(a) >= 48 and ascii(a) <= 57
s += number(a) * weights[i]
else
s += (ascii(a) - 55) * weights[i] ok
next
return d + (10 - (s % 10)) % 10
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Ursala
|
Ursala
|
#import nat
#import flo
nth_non_square = float; plus^/~& math..trunc+ plus/0.5+ sqrt
is_square = sqrt; ^E/~& math..trunc
#show+
examples = %neALP ^(~&,nth_non_square)*t iota23
check = (is_square*~+nth_non_square*t; ~&i&& %eLP)||-[no squares found]-! iota 1000000
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#VBA
|
VBA
|
Sub Main()
Dim i&, c&, j#, s$
Const N& = 1000000
s = "values for n in the range 1 to 22 : "
For i = 1 To 22
s = s & ns(i) & ", "
Next
For i = 1 To N
j = Sqr(ns(i))
If j = CInt(j) Then c = c + 1
Next
Debug.Print s
Debug.Print c & " squares less than " & N
End Sub
Private Function ns(l As Long) As Long
ns = l + Int(1 / 2 + Sqr(l))
End Function
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#Prolog
|
Prolog
|
:- use_module(library(lists)).
set :-
A = [2, 4, 1, 3],
B = [5, 2, 3, 2],
( is_set(A) -> format('~w is a set~n', [A])
; format('~w is not a set~n', [A])),
( is_set(B) -> format('~w is a set~n', [B])
; format('~w is not a set~n', [B])),
% create a set from a list
list_to_set(B, BS),
( is_set(BS) -> format('~nCreate a set from a list~n~w is a set~n', [BS])
; format('~w is not a set~n', [BS])),
intersection(A, BS, I),
format('~n~w intersection ~w => ~w~n', [A, BS, I]),
union(A, BS, U),
format('~w union ~w => ~w~n', [A, BS, U]),
difference(A, BS, D),
format('~w difference ~w => ~w~n', [A, BS, D]),
X = [1,2],
( subset(X, A) -> format('~n~w is a subset of ~w~n', [X, A])
; format('~w is not a subset of ~w~n', [X, A])),
Y = [1,5],
( subset(Y, A) -> format('~w is a subset of ~w~n', [Y, A])
; format('~w is not a subset of ~w~n', [Y, A])),
Z = [1, 2, 3, 4],
( equal(Z, A) -> format('~n~w is equal to ~w~n', [Z, A])
; format('~w is not equal to ~w~n', [Z, A])),
T = [1, 2, 3],
( equal(T, A) -> format('~w is equal to ~w~n', [T, A])
; format('~w is not equal to ~w~n', [T, A])).
% compute difference of sets
difference(A, B, D) :-
exclude(member_(B), A, D).
member_(L, X) :-
member(X, L).
equal([], []).
equal([H1 | T1], B) :-
select(H1, B, B1),
equal(T1, B1).
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#FreeBASIC
|
FreeBASIC
|
' FB 1.05.0
Sub sieve(n As Integer)
If n < 2 Then Return
Dim a(2 To n) As Integer
For i As Integer = 2 To n : a(i) = i : Next
Dim As Integer p = 2, q
' mark non-prime numbers by setting the corresponding array element to 0
Do
For j As Integer = p * p To n Step p
a(j) = 0
Next j
' look for next non-zero element in array after 'p'
q = 0
For j As Integer = p + 1 To Sqr(n)
If a(j) <> 0 Then
q = j
Exit For
End If
Next j
If q = 0 Then Exit Do
p = q
Loop
' print the non-zero numbers remaining i.e. the primes
For i As Integer = 2 To n
If a(i) <> 0 Then
Print Using "####"; a(i);
End If
Next
Print
End Sub
Print "The primes up to 1000 are :"
Print
sieve(1000)
Print
Print "Press any key to quit"
Sleep
|
http://rosettacode.org/wiki/SEDOLs
|
SEDOLs
|
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
Check each input is correctly formed, especially with respect to valid characters allowed in a SEDOL string.
Related tasks
Luhn test
ISIN
|
#Ruby
|
Ruby
|
Sedol_char = "0123456789BCDFGHJKLMNPQRSTVWXYZ"
Sedolweight = [1,3,1,7,3,9]
def char2value(c)
raise ArgumentError, "Invalid char #{c}" unless Sedol_char.include?(c)
c.to_i(36)
end
def checksum(sedol)
raise ArgumentError, "Invalid length" unless sedol.size == Sedolweight.size
sum = sedol.chars.zip(Sedolweight).sum{|ch, weight| char2value(ch) * weight }
((10 - (sum % 10)) % 10).to_s
end
data = %w(710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
C0000
1234567
00000A)
data.each do |sedol|
print "%-8s " % sedol
begin
puts sedol + checksum(sedol)
rescue => e
p e
end
end
|
http://rosettacode.org/wiki/Sequence_of_non-squares
|
Sequence of non-squares
|
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
|
#Wren
|
Wren
|
import "/fmt" for Fmt
System.print("The first 22 numbers in the sequence are:")
System.print(" n term")
for (n in 1...1e6) {
var s = n + (0.5 + n.sqrt).floor
var ss = s.sqrt.round
if (ss * ss == s) {
Fmt.print("The $r number in the sequence $d = $d x $d is a square.", n, s, ss, ss)
return
}
if (n <= 22) Fmt.print(" $2d $2d", n, s)
}
System.print("\nNo squares were found in the first 999,999 terms.")
|
http://rosettacode.org/wiki/Set
|
Set
|
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an element in set S"
A ∪ B -- union; a set of all elements either in set A or in set B.
A ∩ B -- intersection; a set of all elements in both set A and set B.
A ∖ B -- difference; a set of all elements in set A, except those in set B.
A ⊆ B -- subset; true if every element in set A is also in set B.
A = B -- equality; true if every element of set A is in set B and vice versa.
As an option, show some other set operations.
(If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
As another option, show how to modify a mutable set.
One might implement a set using an associative array (with set elements as array keys and some dummy value as the values).
One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bit-wise binary operators).
The basic test, m ∈ S, is O(n) with a sequential list of elements, O(log n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
Stack
|
#PureBasic
|
PureBasic
|
Procedure.s booleanText(b) ;returns 'True' or 'False' for a boolean input
If b: ProcedureReturn "True": EndIf
ProcedureReturn "False"
EndProcedure
Procedure.s listSetElements(Map a(), delimeter.s = " ") ;format elements for display
Protected output$
ForEach a()
output$ + MapKey(a()) + delimeter
Next
ProcedureReturn "(" + RTrim(output$, delimeter) + ")"
EndProcedure
Procedure.s listSortedSetElements(Map a(), delimeter.s = " ") ;format elements for display as sorted for easy comparison
Protected output$
NewList b.s()
ForEach a()
AddElement(b()): b() = MapKey(a())
Next
SortList(b(), #PB_Sort_Ascending | #PB_Sort_NoCase)
ForEach b()
output$ + b() + delimeter
Next
ProcedureReturn "(" + RTrim(output$, delimeter) + ")"
EndProcedure
Procedure cardinalityOf(Map a())
ProcedureReturn MapSize(a())
EndProcedure
Procedure createSet(elements.s, Map o(), delimeter.s = " ", clearSet = 1)
Protected i, elementCount
If clearSet: ClearMap(o()): EndIf
elementCount = CountString(elements, delimeter) + 1 ;add one for the last element which won't have a delimeter
For i = 1 To elementCount
AddMapElement(o(), StringField(elements, i, delimeter))
Next
ProcedureReturn MapSize(o())
EndProcedure
Procedure adjoinTo(elements.s, Map o(), delimeter.s = " ")
ProcedureReturn createSet(elements, o(), delimeter, 0)
EndProcedure
Procedure disjoinFrom(elements.s, Map o(), delimeter.s = " ")
Protected i, elementCount
elementCount = CountString(elements, delimeter) + 1 ;add one for the last element which won't have a delimeter
For i = 1 To elementCount
DeleteMapElement(o(), StringField(elements, i, delimeter))
Next
ProcedureReturn MapSize(o())
EndProcedure
Procedure isElementOf(element.s, Map a())
ProcedureReturn FindMapElement(a(), element)
EndProcedure
Procedure unionOf(Map a(), Map b(), Map o())
CopyMap(a(), o())
ForEach b()
AddMapElement(o(), MapKey(b()))
Next
ProcedureReturn MapSize(o())
EndProcedure
Procedure intersectionOf(Map a(), Map b(), Map o())
ClearMap(o())
ForEach a()
If FindMapElement(b(), MapKey(a()))
AddMapElement(o(), MapKey(a()))
EndIf
Next
ProcedureReturn MapSize(o())
EndProcedure
Procedure differenceOf(Map a(), Map b(), Map o())
CopyMap(a(), o())
ForEach b()
If FindMapElement(o(), MapKey(b()))
DeleteMapElement(o())
Else
AddMapElement(o(), MapKey(b()))
EndIf
Next
ProcedureReturn MapSize(o())
EndProcedure
Procedure isSubsetOf(Map a(), Map b()) ;boolean
ForEach a()
If Not FindMapElement(b(), MapKey(a()))
ProcedureReturn 0
EndIf
Next
ProcedureReturn 1
EndProcedure
Procedure isProperSubsetOf(Map a(), Map b()) ;boolean
If MapSize(a()) = MapSize(b())
ProcedureReturn 0
EndIf
ProcedureReturn isSubsetOf(a(), b())
EndProcedure
Procedure isEqualTo(Map a(), Map b())
If MapSize(a()) = MapSize(b())
ProcedureReturn isSubsetOf(a(), b())
EndIf
ProcedureReturn 0
EndProcedure
Procedure isEmpty(Map a()) ;boolean
If MapSize(a())
ProcedureReturn 0
EndIf
ProcedureReturn 1
EndProcedure
If OpenConsole()
NewMap a()
NewMap b()
NewMap o() ;for output sets
NewMap c()
createSet("red blue green orange yellow", a())
PrintN("Set A = " + listSortedSetElements(a()) + " of cardinality " + Str(cardinalityOf(a())) + ".")
createSet("lady green red", b())
PrintN("Set B = " + listSortedSetElements(b()) + " of cardinality " + Str(cardinalityOf(b())) + ".")
PrintN("'red' is an element of A is " + booleanText(isElementOf("red", a())) + ".")
PrintN("'red' is an element of B is " + booleanText(isElementOf("red", b())) + ".")
PrintN("'blue' is an element of B is " + booleanText(isElementOf("blue", b())) + ".")
unionOf(a(), b(), o())
PrintN(#crlf$ + "Union of A & B is " + listSortedSetElements(o()) + ".")
intersectionOf(a(), b(), o())
PrintN("Intersection of A & B is " + listSortedSetElements(o()) + ".")
differenceOf(a(), b(), o())
PrintN("Difference of A & B is " + listSortedSetElements(o()) + ".")
PrintN(listSortedSetElements(a()) + " equals " + listSortedSetElements(a()) + " is " + booleanText(isEqualTo(a(), a())) + ".")
PrintN(listSortedSetElements(a()) + " equals " + listSortedSetElements(b()) + " is " + booleanText(isEqualTo(a(), b())) + ".")
createSet("red green", c())
PrintN(#crlf$ + listSortedSetElements(c()) + " is a subset of " + listSortedSetElements(a()) + " is "+ booleanText(isSubsetOf(c(), a())) + ".")
PrintN(listSortedSetElements(c()) + " is a proper subset of " + listSortedSetElements(b()) + " is "+ booleanText(isProperSubsetOf(c(), b())) + ".")
PrintN(listSortedSetElements(c()) + " is a proper subset of " + listSortedSetElements(a()) + " is "+ booleanText(isProperSubsetOf(c(), a())) + ".")
PrintN(listSortedSetElements(b()) + " is a proper subset of " + listSortedSetElements(b()) + " is "+ booleanText(isProperSubsetOf(b(), b())) + ".")
PrintN(#crlf$ + "Set C = " + listSortedSetElements(c()) + " of cardinality " + Str(cardinalityOf(c())) + ".")
adjoinTo("dog cat mouse", c())
PrintN("Add 'dog cat mouse' to C to get " + listSortedSetElements(c()) + " of cardinality " + Str(cardinalityOf(c())) + ".")
disjoinFrom("red green dog", c())
PrintN("Take away 'red green dog' from C to get " + listSortedSetElements(c()) + " of cardinality " + Str(cardinalityOf(c())) + ".")
Print(#crlf$ + #crlf$ + "Press ENTER to exit"): Input()
CloseConsole()
EndIf
|
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
|
Sieve of Eratosthenes
|
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.
That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.
If there's an easy way to add such a wheel based optimization, implement it as an alternative version.
Note
It is important that the sieve algorithm be the actual algorithm used to find prime numbers for the task.
Related tasks
Emirp primes
count in factors
prime decomposition
factors of an integer
extensible prime generator
primality by trial division
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Frink
|
Frink
|
n = eval[input["Enter highest number: "]]
results = array[sieve[n]]
println[results]
println[length[results] + " prime numbers less than or equal to " + n]
sieve[n] :=
{
// Initialize array
array = array[0 to n]
array@1 = 0
for i = 2 to ceil[sqrt[n]]
if array@i != 0
for j = i^2 to n step i
array@j = 0
return select[array, { |x| x != 0 }]
}
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.