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http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#Haskell
|
Haskell
|
import Data.List (group, sort)
import Text.Printf (printf)
import Data.Numbers.Primes (primes)
freq :: [(Int, Int)] -> Float
freq xs = realToFrac (length xs) / 100
line :: [(Int, Int)] -> IO ()
line t@((n1, n2):xs) = printf "%d -> %d count: %5d frequency: %2.2f %%\n" n1 n2 (length t) (freq t)
main :: IO ()
main = mapM_ line $ groups primes
where groups = tail . group . sort . (\n -> zip (0: n) n) . fmap (`mod` 10) . take 10000
|
http://rosettacode.org/wiki/Prime_decomposition
|
Prime decomposition
|
The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the prime decomposition of a given number
n
{\displaystyle n}
greater than 1.
If your language does not have an isPrime-like function available,
you may assume that you have a function which determines
whether a number is prime (note its name before your code).
If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes.
Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc).
Related tasks
count in factors
factors of an integer
Sieve of Eratosthenes
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
|
#ALGOL_68
|
ALGOL 68
|
#IF long int possible THEN #
MODE LINT = LONG INT;
LINT lmax int = long max int;
OP LLENG = (INT i)LINT: LENG i,
LSHORTEN = (LINT i)INT: SHORTEN i;
#ELSE
MODE LINT = INT;
LINT lmax int = max int;
OP LLENG = (INT i)LINT: i,
LSHORTEN = (LINT i)INT: i;
FI#
OP LLONG = (INT i)LINT: LLENG i;
MODE YIELDLINT = PROC(LINT)VOID;
PROC (LINT, YIELDLINT)VOID gen decompose;
INT upb cache = bits width;
BITS cache := 2r0;
BITS cached := 2r0;
PROC is prime = (LINT n)BOOL: (
BOOL
has factor := FALSE,
out := TRUE;
# FOR LINT factor IN # gen decompose(n, # ) DO ( #
## (LINT factor)VOID:(
IF has factor THEN out := FALSE; GO TO done FI;
has factor := TRUE
# OD # ));
done: out
);
PROC is prime cached := (LINT n)BOOL: (
LINT l half n = n OVER LLONG 2 - LLONG 1;
IF l half n <= LLENG upb cache THEN
INT half n = LSHORTEN l half n;
IF half n ELEM cached THEN
BOOL(half n ELEM cache)
ELSE
BOOL out = is prime(n);
BITS mask = 2r1 SHL (upb cache - half n);
cached := cached OR mask;
IF out THEN cache := cache OR mask FI;
out
FI
ELSE
is prime(n) # above useful cache limit #
FI
);
PROC gen primes := (YIELDLINT yield)VOID:(
yield(LLONG 2);
LINT n := LLONG 3;
WHILE n < l maxint - LLONG 2 DO
yield(n);
n +:= LLONG 2;
WHILE n < l maxint - LLONG 2 AND NOT is prime cached(n) DO
n +:= LLONG 2
OD
OD
);
# PROC # gen decompose := (LINT in n, YIELDLINT yield)VOID: (
LINT n := in n;
# FOR LINT p IN # gen primes( # ) DO ( #
## (LINT p)VOID:
IF p*p > n THEN
GO TO done
ELSE
WHILE n MOD p = LLONG 0 DO
yield(p);
n := n OVER p
OD
FI
# OD # );
done:
IF n > LLONG 1 THEN
yield(n)
FI
);
main:(
# FOR LINT m IN # gen primes( # ) DO ( #
## (LINT m)VOID:(
LINT p = LLONG 2 ** LSHORTEN m - LLONG 1;
print(("2**",whole(m,0),"-1 = ",whole(p,0),", with factors:"));
# FOR LINT factor IN # gen decompose(p, # ) DO ( #
## (LINT factor)VOID:
print((" ",whole(factor,0)))
# OD # );
print(new line);
IF m >= LLONG 59 THEN GO TO done FI
# OD # ));
done: EMPTY
)
|
http://rosettacode.org/wiki/Polyspiral
|
Polyspiral
|
A Polyspiral is a spiral made of multiple line segments, whereby each segment is larger (or smaller) than the previous one by a given amount. Each segment also changes direction at a given angle.
Task
Animate a series of polyspirals, by drawing a complete spiral then incrementing the angle, and (after clearing the background) drawing the next, and so on. Every spiral will be a frame of the animation. The animation may stop as it goes full circle or continue indefinitely. The given input values may be varied.
If animation is not practical in your programming environment, you may show a single frame instead.
Pseudo code
set incr to 0.0
// animation loop
WHILE true
incr = (incr + 0.05) MOD 360
x = width / 2
y = height / 2
length = 5
angle = incr
// spiral loop
FOR 1 TO 150
drawline
change direction by angle
length = length + 3
angle = (angle + incr) MOD 360
ENDFOR
|
#AutoHotkey
|
AutoHotkey
|
If !pToken := Gdip_Startup()
{
MsgBox, 48, gdiplus error!, Gdiplus failed to start. Please ensure you have gdiplus on your system
ExitApp
}
OnExit, Exit
gdip1()
incr := 0
π := 3.141592653589793
loop
{
incr := Mod(incr + 0.05, 360)
x1 := Width/2
y1 := Height/2
length := 5
angle := incr
Gdip_FillRoundedRectangle(G, pBrush, 0, 0, Width, Height, 0)
loop 150
{
x2 := x1 + length * Cos(angle * π/180)
y2 := y1 + length * Sin(angle * π/180)
Gdip_DrawLine(G, pPen, x1, y1, x2, y2)
x1 := x2
y1 := y2
length := length + 3
angle := Mod(angle + incr, 360)
}
UpdateLayeredWindow(hwnd1, hdc, -1, -1, Width, Height)
Sleep 25
}
return
;----------------------------------------------------------------
Esc:: Pause, toggle
^Esc::ExitApp
;----------------------------------------------------------------
gdip1(){
global
Width := A_ScreenWidth+1, Height := A_ScreenHeight+1
Gui, 1: -Caption +E0x80000 +LastFound +OwnDialogs +Owner +AlwaysOnTop
Gui, 1: Show, NA
hwnd1 := WinExist()
hbm := CreateDIBSection(Width, Height)
hdc := CreateCompatibleDC()
obm := SelectObject(hdc, hbm)
G := Gdip_GraphicsFromHDC(hdc)
Gdip_SetSmoothingMode(G, 4)
pBrush := Gdip_BrushCreateSolid("0xFF000000")
pPen := Gdip_CreatePen("0xFF00FF00", 1)
}
;----------------------------------------------------------------
gdip2(){
global
Gdip_DeletePen(pPen)
Gdip_DeleteBrush(pBrush)
SelectObject(hdc, obm)
DeleteObject(hbm)
DeleteDC(hdc)
Gdip_DeleteGraphics(G)
}
;----------------------------------------------------------------
Exit:
gdip2()
Gdip_Shutdown(pToken)
ExitApp
Return
;----------------------------------------------------------------
|
http://rosettacode.org/wiki/Primality_by_trial_division
|
Primality by trial division
|
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
count in factors
prime decomposition
AKS test for primes
factors of an integer
Sieve of Eratosthenes
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#AArch64_Assembly
|
AArch64 Assembly
|
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program testPrime64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM64.inc"
/*******************************************/
/* Initialized data */
/*******************************************/
.data
szMessStartPgm: .asciz "Program start \n"
szMessEndPgm: .asciz "Program normal end.\n"
szMessNotPrime: .asciz "Not prime.\n"
szMessPrime: .asciz "Prime\n"
szCarriageReturn: .asciz "\n"
/*******************************************/
/* UnInitialized data */
/*******************************************/
.bss
.align 4
/*******************************************/
/* code section */
/*******************************************/
.text
.global main
main: // program start
ldr x0,qAdrszMessStartPgm // display start message
bl affichageMess
ldr x0,qVal
bl isPrime // test prime ?
cmp x0,#0
beq 1f
ldr x0,qAdrszMessPrime // yes
bl affichageMess
b 2f
1:
ldr x0,qAdrszMessNotPrime // no
bl affichageMess
2:
ldr x0,qAdrszMessEndPgm // display end message
bl affichageMess
100: // standard end of the program
mov x0,0 // return code
mov x8,EXIT // request to exit program
svc 0 // perform system call
qAdrszMessStartPgm: .quad szMessStartPgm
qAdrszMessEndPgm: .quad szMessEndPgm
qAdrszCarriageReturn: .quad szCarriageReturn
qAdrszMessNotPrime: .quad szMessNotPrime
qAdrszMessPrime: .quad szMessPrime
//qVal: .quad 1042441 // test not prime
//qVal: .quad 1046527 // test prime
//qVal: .quad 37811 // test prime
//qVal: .quad 1429671721 // test not prime (37811 * 37811)
qVal: .quad 100000004437 // test prime
/******************************************************************/
/* test if number is prime */
/******************************************************************/
/* x0 contains the number */
/* x0 return 1 if prime else return 0 */
isPrime:
stp x1,lr,[sp,-16]! // save registers
cmp x0,1 // <= 1 ?
ble 98f
cmp x0,3 // 2 and 3 prime
ble 97f
tst x0,1 // even ?
beq 98f
mov x11,3 // first divisor
1:
udiv x12,x0,x11
msub x13,x12,x11,x0 // compute remainder
cbz x13,98f // end if zero
add x11,x11,#2 // increment divisor
cmp x11,x12 // divisors<=quotient ?
ble 1b // loop
97:
mov x0,1 // return prime
b 100f
98:
mov x0,0 // not prime
b 100f
100:
ldp x1,lr,[sp],16 // restaur 2 registers
ret // return to address lr x30
/********************************************************/
/* File Include fonctions */
/********************************************************/
/* for this file see task include a file in language AArch64 assembly */
.include "../includeARM64.inc"
|
http://rosettacode.org/wiki/Price_fraction
|
Price fraction
|
A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 and 1.00, rescale according to the following table:
>= 0.00 < 0.06 := 0.10
>= 0.06 < 0.11 := 0.18
>= 0.11 < 0.16 := 0.26
>= 0.16 < 0.21 := 0.32
>= 0.21 < 0.26 := 0.38
>= 0.26 < 0.31 := 0.44
>= 0.31 < 0.36 := 0.50
>= 0.36 < 0.41 := 0.54
>= 0.41 < 0.46 := 0.58
>= 0.46 < 0.51 := 0.62
>= 0.51 < 0.56 := 0.66
>= 0.56 < 0.61 := 0.70
>= 0.61 < 0.66 := 0.74
>= 0.66 < 0.71 := 0.78
>= 0.71 < 0.76 := 0.82
>= 0.76 < 0.81 := 0.86
>= 0.81 < 0.86 := 0.90
>= 0.86 < 0.91 := 0.94
>= 0.91 < 0.96 := 0.98
>= 0.96 < 1.01 := 1.00
|
#AppleScript
|
AppleScript
|
-- This handler just returns the standardised real value. It's up to external processes to format it for display.
on standardisePrice(input)
set integerPart to input div 1.0
set fractionalPart to input mod 1.0
if (fractionalPart is 0.0) then
return input as real
else if (fractionalPart < 0.06) then
return integerPart + 0.1
else if (fractionalPart < 0.16) then
return integerPart + 0.18 + (fractionalPart - 0.06) div 0.05 * 0.08
else if (fractionalPart < 0.36) then
return integerPart + 0.32 + (fractionalPart - 0.16) div 0.05 * 0.06
else if (fractionalPart < 0.96) then
return integerPart + 0.54 + (fractionalPart - 0.36) div 0.05 * 0.04
else
return integerPart + 1.0
end if
end standardisePrice
-- Test code:
set originals to {}
set standardised to {}
repeat 20 times
set price to (random number 100) / 100
set end of originals to text 2 thru -2 of ((price + 10.001) as text)
set end of standardised to text 2 thru -2 of ((standardisePrice(price) + 10.001) as text)
end repeat
set astid to AppleScript's text item delimiters
set AppleScript's text item delimiters to ", "
set output to linefeed & "Originals: " & originals & linefeed & "Standardised: " & standardised
set AppleScript's text item delimiters to astid
return output
|
http://rosettacode.org/wiki/Proper_divisors
|
Proper divisors
|
The proper divisors of a positive integer N are those numbers, other than N itself, that divide N without remainder.
For N > 1 they will always include 1, but for N == 1 there are no proper divisors.
Examples
The proper divisors of 6 are 1, 2, and 3.
The proper divisors of 100 are 1, 2, 4, 5, 10, 20, 25, and 50.
Task
Create a routine to generate all the proper divisors of a number.
use it to show the proper divisors of the numbers 1 to 10 inclusive.
Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has.
Show all output here.
Related tasks
Amicable pairs
Abundant, deficient and perfect number classifications
Aliquot sequence classifications
Factors of an integer
Prime decomposition
|
#Component_Pascal
|
Component Pascal
|
MODULE RosettaProperDivisor;
IMPORT StdLog;
PROCEDURE Pd*(n: LONGINT;OUT r: ARRAY OF LONGINT):LONGINT;
VAR
i,j: LONGINT;
BEGIN
i := 1;j := 0;
IF n > 1 THEN
WHILE (i < n) DO
IF (n MOD i) = 0 THEN
IF (j < LEN(r)) THEN r[j] := i END; INC(j)
END;
INC(i)
END;
END;
RETURN j
END Pd;
PROCEDURE Do*;
VAR
r: ARRAY 128 OF LONGINT;
i,j,found,max,idxMx: LONGINT;
mx: ARRAY 128 OF LONGINT;
BEGIN
FOR i := 1 TO 10 DO
found := Pd(i,r);
IF found > LEN(r) THEN (* Error. more pd than r can admit *) HALT(1) END;
StdLog.Int(i);StdLog.String("[");StdLog.Int(found);StdLog.String("]:> ");
FOR j := 0 TO found - 1 DO
StdLog.Int(r[j]);StdLog.Char(' ');
END;
StdLog.Ln
END;
max := 0;idxMx := 0;
FOR i := 1 TO 20000 DO
found := Pd(i,r);
IF found > max THEN
idxMx:= 0;mx[idxMx] := i;max := found
ELSIF found = max THEN
INC(idxMx);mx[idxMx] := i
END;
END;
StdLog.String("Found: ");StdLog.Int(idxMx + 1);
StdLog.String(" Numbers with the longest proper divisors [");
StdLog.Int(max);StdLog.String("]: ");StdLog.Ln;
FOR i := 0 TO idxMx DO
StdLog.Int(mx[i]);StdLog.Ln
END
END Do;
END RosettaProperDivisor.
^Q RosettaProperDivisor.Do~
|
http://rosettacode.org/wiki/Probabilistic_choice
|
Probabilistic choice
|
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is involved, this is subject to rounding errors).
aleph 1/5.0
beth 1/6.0
gimel 1/7.0
daleth 1/8.0
he 1/9.0
waw 1/10.0
zayin 1/11.0
heth 1759/27720 # adjusted so that probabilities add to 1
Related task
Random number generator (device)
|
#ERRE
|
ERRE
|
PROGRAM PROB_CHOICE
DIM ITEM$[7],PROB[7],CNT[7]
BEGIN
ITEM$[]=("aleph","beth","gimel","daleth","he","waw","zayin","heth")
PROB[0]=1/5.0 PROB[1]=1/6.0 PROB[2]=1/7.0 PROB[3]=1/8.0
PROB[4]=1/9.0 PROB[5]=1/10.0 PROB[6]=1/11.0 PROB[7]=1759/27720
SUM=0
FOR I%=0 TO UBOUND(PROB,1) DO
SUM=SUM+PROB[I%]
END FOR
IF ABS(SUM-1)>1E-6 THEN
PRINT("Probabilities don't sum to 1")
ELSE
FOR TRIAL=1 TO 1E6 DO
R=RND(1)
P=0
FOR I%=0 TO UBOUND(PROB,1) DO
P+=PROB[I%]
IF R<P THEN
CNT[I%]+=1
EXIT
END IF
END FOR
END FOR
PRINT("Item actual theoretical")
PRINT("---------------------------------")
FOR I%=0 TO UBOUND(ITEM$,1) DO
WRITE("\ \ #.###### #.######";ITEM$[I%],CNT[I%]/1E6,PROB[I%])
END FOR
END IF
END PROGRAM
|
http://rosettacode.org/wiki/Probabilistic_choice
|
Probabilistic choice
|
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is involved, this is subject to rounding errors).
aleph 1/5.0
beth 1/6.0
gimel 1/7.0
daleth 1/8.0
he 1/9.0
waw 1/10.0
zayin 1/11.0
heth 1759/27720 # adjusted so that probabilities add to 1
Related task
Random number generator (device)
|
#Euphoria
|
Euphoria
|
constant MAX = #3FFFFFFF
constant times = 1e6
atom d,e
sequence Mapps
Mapps = {
{ "aleph", 1/5, 0},
{ "beth", 1/6, 0},
{ "gimel", 1/7, 0},
{ "daleth", 1/8, 0},
{ "he", 1/9, 0},
{ "waw", 1/10, 0},
{ "zayin", 1/11, 0},
{ "heth", 1759/27720, 0}
}
for i = 1 to times do
d = (rand(MAX)-1)/MAX
e = 0
for j = 1 to length(Mapps) do
e += Mapps[j][2]
if d <= e then
Mapps[j][3] += 1
exit
end if
end for
end for
printf(1,"Sample times: %d\n",times)
for j = 1 to length(Mapps) do
d = Mapps[j][3]/times
printf(1,"%-7s should be %f is %f | Deviatation %6.3f%%\n",
{Mapps[j][1],Mapps[j][2],d,(1-Mapps[j][2]/d)*100})
end for
|
http://rosettacode.org/wiki/Primes_-_allocate_descendants_to_their_ancestors
|
Primes - allocate descendants to their ancestors
|
The concept, is to add the decomposition into prime factors of a number to get its 'ancestors'.
The objective is to demonstrate that the choice of the algorithm can be crucial in term of performance.
This solution could be compared to the solution that would use the decomposition into primes for all the numbers between 1 and 333.
The problem is to list, for a delimited set of ancestors (from 1 to 99) :
- the total of their own ancestors (LEVEL),
- their own ancestors (ANCESTORS),
- the total of the direct descendants (DESCENDANTS),
- all the direct descendants.
You only have to consider the prime factors < 100.
A grand total of the descendants has to be printed at the end of the list.
The task should be accomplished in a reasonable time-frame.
Example :
46 = 2*23 --> 2+23 = 25, is the parent of 46.
25 = 5*5 --> 5+5 = 10, is the parent of 25.
10 = 2*5 --> 2+5 = 7, is the parent of 10.
7 is a prime factor and, as such, has no parent.
46 has 3 ancestors (7, 10 and 25).
46 has 557 descendants.
The list layout and the output for Parent [46] :
[46] Level: 3
Ancestors: 7, 10, 25
Descendants: 557
129, 205, 246, 493, 518, 529, 740, 806, 888, 999, 1364, 1508, 1748, 2552, 2871, 3128, 3255, 3472, 3519, 3875, 3906, 4263, 4650, 4960, 5075, 5415, 5580, 5776, 5952, 6090, 6279, 6496, 6498, 6696, 6783, 7250, 7308, 7475, 7533, 8075, 8151, 8619, 8700, 8855, 8970, 9280, 9568, 9690, 10115, 10336, 10440, 10626, 10764, 11136, 11495, 11628, 11745, 12103, 12138, 12155, 12528, 12650, 13794, 14094, 14399, 14450, 14586, 15180, 15379, 15778, 16192, 17290, 17303, 17340, 18216, 18496, 20482, 20493, 20570, 20748, 20808, 21658, 21970, 22540, 23409, 24684, 24700, 26026, 26364, 27048, 29260, 29282, 29640, 30429, 30940, 31616, 32200, 33345, 35112, 35568, 36225, 36652, 37128, 37180, 38640, 39501, 40014, 41216, 41769, 41800, 43125, 43470, 44044, 44200, 44616, 46000, 46368, 47025, 49725, 50160, 50193, 51750, 52136, 52164, 52360, 53040, 53504, 55200, 56430, 56576, 58653, 58880, 58905, 59670, 60192, 62100, 62832, 62920, 63648, 66240, 66248, 67716, 69825, 70125, 70656, 70686, 70785, 71604, 74480, 74520, 74529, 74536, 74800, 75504, 79488, 83125, 83790, 83835, 83853, 84150, 84942, 87465, 88725, 89376, 89424, 89760, 93296, 94640, 95744, 99750, 99825, 100548, 100602, 100980, 104125, 104958, 105105, 105625, 106400, 106470, 106480, 107712, 112112, 113568, 118750, 119700, 119790, 121176, 124509, 124950, 125125, 126126, 126750, 127680, 127764, 127776, 133280, 135200, 136192, 136323, 142500, 143640, 143748, 148225, 148750, 149940, 150150, 152000, 152100, 153216, 156065, 159936, 160160, 161595, 162240, 171000, 172368, 173056, 177870, 178500, 178750, 179928, 180180, 182400, 182520, 184877, 187278, 189728, 190400, 192192, 192375, 193914, 194560, 194688, 202419, 205200, 205335, 211750, 212500, 213444, 214200, 214500, 216216, 218880, 219024, 222950, 228480, 228800, 230850, 233472, 240975, 243243, 243712, 246240, 246402, 254100, 255000, 257040, 257400, 262656, 264110, 267540, 271040, 272000, 274176, 274560, 277020, 285376, 286875, 289170, 289575, 292864, 295488, 302500, 304920, 306000, 308448, 308880, 316932, 318500, 321048, 325248, 326400, 329472, 332424, 343035, 344250, 347004, 347490, 348160, 361179, 363000, 365904, 367200, 370656, 373977, 377300, 382200, 387200, 391680, 407680, 408375, 411642, 413100, 416988, 417792, 429975, 435600, 440640, 452760, 455000, 458640, 464640, 470016, 470596, 482944, 489216, 490050, 495616, 495720, 509355, 511875, 515970, 522720, 528768, 539000, 543312, 546000, 550368, 557568, 557685, 582400, 588060, 594864, 606375, 609375, 611226, 614250, 619164, 627264, 646800, 650000, 655200, 669222, 672280, 689920, 698880, 705672, 721875, 727650, 731250, 737100, 745472, 756315, 770000, 776160, 780000, 786240, 793881, 806736, 827904, 832000, 838656, 859375, 866250, 873180, 877500, 884520, 900375, 907578, 924000, 931392, 936000, 943488, 960400, 985600, 995085, 998400, 1031250, 1039500, 1047816, 1053000, 1061424, 1064960, 1071875, 1080450, 1100000, 1108800, 1123200, 1152480, 1178793, 1182720, 1184625, 1194102, 1198080, 1229312, 1237500, 1247400, 1261568, 1263600, 1277952, 1286250, 1296540, 1320000, 1330560, 1347840, 1372000, 1382976, 1403325, 1408000, 1419264, 1421550, 1437696, 1485000, 1496880, 1516320, 1531250, 1543500, 1555848, 1584000, 1596672, 1617408, 1646400, 1670625, 1683990, 1689600, 1705860, 1750329, 1756160, 1782000, 1796256, 1802240, 1819584, 1837500, 1852200, 1900800, 1960000, 1975680, 2004750, 2020788, 2027520, 2047032, 2083725, 2107392, 2138400, 2162688, 2187500, 2205000, 2222640, 2280960, 2302911, 2352000, 2370816, 2405700, 2433024, 2480625, 2500470, 2508800, 2566080, 2625000, 2646000, 2667168, 2737152, 2800000, 2822400, 2886840, 2953125, 2976750, 3000564, 3010560, 3079296, 3125000, 3150000, 3175200, 3211264, 3247695, 3360000, 3386880, 3464208, 3515625, 3543750, 3572100, 3584000, 3612672, 3750000, 3780000, 3810240, 3897234, 4000000, 4032000, 4064256, 4218750, 4252500, 4286520, 4300800, 4500000, 4536000, 4572288, 4587520, 4800000, 4822335, 4838400, 5062500, 5103000, 5120000, 5143824, 5160960, 5400000, 5443200, 5505024, 5740875, 5760000, 5786802, 5806080, 6075000, 6123600, 6144000, 6193152, 6480000, 6531840, 6553600, 6834375, 6889050, 6912000, 6967296, 7290000, 7348320, 7372800, 7776000, 7838208, 7864320, 8201250, 8266860, 8294400, 8388608, 8748000, 8817984, 8847360, 9331200, 9437184, 9841500, 9920232, 9953280, 10497600, 10616832, 11160261, 11197440, 11809800, 11943936, 12597120, 13286025, 13436928, 14171760, 15116544, 15943230, 17006112, 19131876
Some figures :
The biggest descendant number : 3^33 = 5.559.060.566.555.523 (parent 99)
Total Descendants 546.986
|
#Sidef
|
Sidef
|
var maxsum = 99
var primes = maxsum.primes
var descendants = (maxsum+1).of { [] }
var ancestors = (maxsum+1).of { [] }
for p in (primes) {
descendants[p] << p
for s in (1 .. descendants.end-p) {
descendants[s + p] << descendants[s].map {|q| p*q }...
}
}
for p in (primes + [4]) {
descendants[p].pop
}
var total = 0
for s in (1 .. maxsum) {
descendants[s].sort!
total += (var dsclen = descendants[s].len)
var idx = descendants[s].first_index {|x| x > maxsum }
for d in (descendants[s].slice(0, idx)) {
ancestors[d] = (ancestors[s] + [s])
}
if ((s <= 20) || (s ~~ [46, 74, 99])) {
printf("%2d: %d Ancestor(s): %-15s %5s Descendant(s): %s\n", s,
ancestors[s].len, "[#{ancestors[s].join(' ')}]", descendants[s].len,
dsclen <= 10 ? descendants[s] : "[#{descendants[s].first(10).join(' ')} ...]")
}
}
say "\nTotal descendants: #{total}"
|
http://rosettacode.org/wiki/Priority_queue
|
Priority queue
|
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order.
Task
Create a priority queue. The queue must support at least two operations:
Insertion. An element is added to the queue with a priority (a numeric value).
Top item removal. Deletes the element or one of the elements with the current top priority and return it.
Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc.
To test your implementation, insert a number of elements into the queue, each with some random priority.
Then dequeue them sequentially; now the elements should be sorted by priority.
You can use the following task/priority items as input data:
Priority Task
══════════ ════════════════
3 Clear drains
4 Feed cat
5 Make tea
1 Solve RC tasks
2 Tax return
The implementation should try to be efficient. A typical implementation has O(log n) insertion and extraction time, where n is the number of items in the queue.
You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc. If so, discuss the reasons behind it.
|
#Delphi
|
Delphi
|
program Priority_queue;
{$APPTYPE CONSOLE}
uses
System.SysUtils, Boost.Generics.Collection;
var
Queue: TPriorityQueue<String>;
begin
Queue := TPriorityQueue<String>.Create(['Clear drains', 'Feed cat',
'Make tea', 'Solve RC tasks', 'Tax return'], [3, 4, 5, 1, 2]);
while not Queue.IsEmpty do
with Queue.DequeueEx do
Writeln(Priority, ', ', value);
end.
|
http://rosettacode.org/wiki/Problem_of_Apollonius
|
Problem of Apollonius
|
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the example in the code are shown in the diagram (below and to the right).
The red circle is "internally tangent" to all three black circles, and the green circle is "externally tangent" to all three black circles.
|
#Julia
|
Julia
|
using Printf
module ApolloniusProblems
using Polynomials
export Circle
struct Point{T<:Real}
x::T
y::T
end
xcoord(p::Point) = p.x
ycoord(p::Point) = p.y
struct Circle{T<:Real}
c::Point{T}
r::T
end
Circle(x::T, y::T, r::T) where T<:Real = Circle(Point(x, y), r)
radius(c::Circle) = c.r
center(c::Circle) = c.c
xcenter(c::Circle) = xcoord(center(c))
ycenter(c::Circle) = ycoord(center(c))
Base.show(io::IO, c::Circle) =
@printf(io, "centered at (%0.4f, %0.4f) with radius %0.4f",
xcenter(c), ycenter(c), radius(c))
function solve(ap::Vector{Circle{T}}, enc=()) where T<:Real
length(ap) == 3 || error("This Apollonius problem needs 3 circles.")
x = @. xcenter(ap)
y = @. ycenter(ap)
r = map(u -> ifelse(u ∈ enc, -1, 1), 1:3) .* radius.(ap)
@views begin
a = 2x[1] .- 2x[2:3]
b = 2y[1] .- 2y[2:3]
c = 2r[1] .- 2r[2:3]
d = (x[1] ^ 2 + y[1] ^ 2 - r[1] ^ 2) .- (x[2:3] .^ 2 .+ y[2:3] .^ 2 .- r[2:3] .^ 2)
end
u = Poly([-det([b d]), det([b c])] ./ det([a b]))
v = Poly([det([a d]), -det([a c])] ./ det([a b]))
w = Poly([r[1], 1.0]) ^ 2
s = (u - x[1]) ^ 2 + (v - y[1]) ^ 2 - w
r = filter(x -> iszero(imag(x)) && x > zero(x), roots(s))
length(r) < 2 || error("The solution is not unique.")
length(r) == 1 || error("There is no solution.")
r = r[1]
return Circle(polyval(u, r), polyval(v, r), r)
end
end # module ApolloniusProblem
|
http://rosettacode.org/wiki/Problem_of_Apollonius
|
Problem of Apollonius
|
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the example in the code are shown in the diagram (below and to the right).
The red circle is "internally tangent" to all three black circles, and the green circle is "externally tangent" to all three black circles.
|
#Kotlin
|
Kotlin
|
// version 1.1.3
data class Circle(val x: Double, val y: Double, val r: Double)
val Double.sq get() = this * this
fun solveApollonius(c1: Circle, c2: Circle, c3: Circle,
s1: Int, s2: Int, s3: Int): Circle {
val (x1, y1, r1) = c1
val (x2, y2, r2) = c2
val (x3, y3, r3) = c3
val v11 = 2 * x2 - 2 * x1
val v12 = 2 * y2 - 2 * y1
val v13 = x1.sq - x2.sq + y1.sq - y2.sq - r1.sq + r2.sq
val v14 = 2 * s2 * r2 - 2 * s1 * r1
val v21 = 2 * x3 - 2 * x2
val v22 = 2 * y3 - 2 * y2
val v23 = x2.sq - x3.sq + y2.sq - y3.sq - r2.sq + r3.sq
val v24 = 2 * s3 * r3 - 2 * s2 * r2
val w12 = v12 / v11
val w13 = v13 / v11
val w14 = v14 / v11
val w22 = v22 / v21 - w12
val w23 = v23 / v21 - w13
val w24 = v24 / v21 - w14
val p = -w23 / w22
val q = w24 / w22
val m = -w12 * p - w13
val n = w14 - w12 * q
val a = n.sq + q.sq - 1
val b = 2 * m * n - 2 * n * x1 + 2 * p * q - 2 * q * y1 + 2 * s1 * r1
val c = x1.sq + m.sq - 2 * m * x1 + p.sq + y1.sq - 2 * p * y1 - r1.sq
val d = b.sq - 4 * a * c
val rs = (-b - Math.sqrt(d)) / (2 * a)
val xs = m + n * rs
val ys = p + q * rs
return Circle(xs, ys, rs)
}
fun main(args: Array<String>) {
val c1 = Circle(0.0, 0.0, 1.0)
val c2 = Circle(4.0, 0.0, 1.0)
val c3 = Circle(2.0, 4.0, 2.0)
println(solveApollonius(c1, c2, c3, 1, 1, 1))
println(solveApollonius(c1, c2, c3,-1,-1,-1))
}
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#Phixmonti
|
Phixmonti
|
argument 1 get ?
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#PHP
|
PHP
|
<?php
$program = $_SERVER["SCRIPT_NAME"];
echo "Program: $program\n";
?>
|
http://rosettacode.org/wiki/Pythagorean_triples
|
Pythagorean triples
|
A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displaystyle a,b,c}
are co-prime, that is, if their pairwise greatest common divisors
g
c
d
(
a
,
b
)
=
g
c
d
(
a
,
c
)
=
g
c
d
(
b
,
c
)
=
1
{\displaystyle {\rm {gcd}}(a,b)={\rm {gcd}}(a,c)={\rm {gcd}}(b,c)=1}
.
Because of their relationship through the Pythagorean theorem, a, b, and c are co-prime if a and b are co-prime (
g
c
d
(
a
,
b
)
=
1
{\displaystyle {\rm {gcd}}(a,b)=1}
).
Each triple forms the length of the sides of a right triangle, whose perimeter is
P
=
a
+
b
+
c
{\displaystyle P=a+b+c}
.
Task
The task is to determine how many Pythagorean triples there are with a perimeter no larger than 100 and the number of these that are primitive.
Extra credit
Deal with large values. Can your program handle a maximum perimeter of 1,000,000? What about 10,000,000? 100,000,000?
Note: the extra credit is not for you to demonstrate how fast your language is compared to others; you need a proper algorithm to solve them in a timely manner.
Related tasks
Euler's sum of powers conjecture
List comprehensions
Pythagorean quadruples
|
#Phix
|
Phix
|
with javascript_semantics
atom total, prim, maxPeri = 10
procedure tri(atom s0, s1, s2)
atom p = s0 + s1 + s2
if p<=maxPeri then
prim += 1
total += floor(maxPeri/p)
tri( s0+2*(-s1+s2), 2*( s0+s2)-s1, 2*( s0-s1+s2)+s2);
tri( s0+2*( s1+s2), 2*( s0+s2)+s1, 2*( s0+s1+s2)+s2);
tri(-s0+2*( s1+s2), 2*(-s0+s2)+s1, 2*(-s0+s1+s2)+s2);
end if
end procedure
while maxPeri<=1e8 do
prim := 0;
total := 0;
tri(3, 4, 5);
printf(1,"Up to %d: %d triples, %d primitives.\n", {maxPeri,total,prim})
maxPeri *= 10;
end while
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#Nim
|
Nim
|
if problem1:
quit QuitFailure
if problem2:
quit "There is a problem", QuitFailure
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#Oberon-2
|
Oberon-2
|
IF problem THEN
HALT(1)
END
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#Erlang
|
Erlang
|
#! /usr/bin/escript
isprime(N) when N < 2 -> false;
isprime(N) when N band 1 =:= 0 -> N =:= 2;
isprime(N) -> fac_mod(N - 1, N) =:= N - 1.
fac_mod(N, M) -> fac_mod(N, M, 1).
fac_mod(1, _, A) -> A;
fac_mod(N, M, A) -> fac_mod(N - 1, M, A*N rem M).
main(_) ->
io:format("The first few primes (via Wilson's theorem) are: ~n~p~n",
[[K || K <- lists:seq(1, 128), isprime(K)]]).
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#F.23
|
F#
|
// Wilsons theorem. Nigel Galloway: August 11th., 2020
let wP(n,g)=(n+1I)%g=0I
let fN=Seq.unfold(fun(n,g)->Some((n,g),((n*g),(g+1I))))(1I,2I)|>Seq.filter wP
fN|>Seq.take 120|>Seq.iter(fun(_,n)->printf "%A " n);printfn "\n"
fN|>Seq.skip 999|>Seq.take 15|>Seq.iter(fun(_,n)->printf "%A " n);printfn ""
|
http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#J
|
J
|
/:~ (~.,. ' ',. ":@(%/&1 999999)@(#/.~)) 2 (,'->',])&":/\ 10|p:i.1e6
1->1 42853 0.042853
1->3 77475 0.0774751
1->7 79453 0.0794531
1->9 50153 0.0501531
2->3 1 1e_6
3->1 58255 0.0582551
3->3 39668 0.039668
3->5 1 1e_6
3->7 72827 0.0728271
3->9 79358 0.0793581
5->7 1 1e_6
7->1 64230 0.0642301
7->3 68595 0.0685951
7->7 39603 0.039603
7->9 77586 0.0775861
9->1 84596 0.0845961
9->3 64371 0.0643711
9->7 58130 0.0581301
9->9 42843 0.042843
|
http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#Java
|
Java
|
public class PrimeConspiracy {
public static void main(String[] args) {
final int limit = 1000_000;
final int sieveLimit = 15_500_000;
int[][] buckets = new int[10][10];
int prevDigit = 2;
boolean[] notPrime = sieve(sieveLimit);
for (int n = 3, primeCount = 1; primeCount < limit; n++) {
if (notPrime[n])
continue;
int digit = n % 10;
buckets[prevDigit][digit]++;
prevDigit = digit;
primeCount++;
}
for (int i = 0; i < 10; i++) {
for (int j = 0; j < 10; j++) {
if (buckets[i][j] != 0) {
System.out.printf("%d -> %d : %2f%n", i,
j, buckets[i][j] / (limit / 100.0));
}
}
}
}
public static boolean[] sieve(int limit) {
boolean[] composite = new boolean[limit];
composite[0] = composite[1] = true;
int max = (int) Math.sqrt(limit);
for (int n = 2; n <= max; n++) {
if (!composite[n]) {
for (int k = n * n; k < limit; k += n) {
composite[k] = true;
}
}
}
return composite;
}
}
|
http://rosettacode.org/wiki/Prime_decomposition
|
Prime decomposition
|
The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the prime decomposition of a given number
n
{\displaystyle n}
greater than 1.
If your language does not have an isPrime-like function available,
you may assume that you have a function which determines
whether a number is prime (note its name before your code).
If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes.
Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc).
Related tasks
count in factors
factors of an integer
Sieve of Eratosthenes
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
|
#ALGOL-M
|
ALGOL-M
|
BEGIN
INTEGER I, K, NFOUND;
INTEGER ARRAY FACTORS[1:16];
COMMENT COMPUTE P MOD Q;
INTEGER FUNCTION MOD (P, Q);
INTEGER P, Q;
BEGIN
MOD := P - Q * (P / Q);
END;
COMMENT
FIND THE PRIME FACTORS OF N AND STORE IN THE EXTERNAL
ARRAY "FACTORS", RETURNING THE NUMBER FOUND. IF N IS
PRIME, IT WILL BE STORED AS THE FIRST AND ONLY FACTOR;
INTEGER FUNCTION PRIMEFACTORS(N);
INTEGER N;
BEGIN
INTEGER P, COUNT;
P := 2;
COUNT := 1;
WHILE N >= P * P DO
BEGIN
IF MOD(N, P) = 0 THEN
BEGIN
FACTORS[COUNT] := P;
COUNT := COUNT + 1;
N := N / P;
END
ELSE
P := P + 1;
END;
FACTORS[COUNT] := N;
PRIMEFACTORS := COUNT;
END;
COMMENT -- EXERCISE THE ROUTINE;
FOR I := 77 STEP 2 UNTIL 99 DO
BEGIN
WRITE(I,":");
NFOUND := PRIMEFACTORS(I);
FOR K := 1 STEP 1 UNTIL NFOUND DO
BEGIN
WRITEON(FACTORS[K]);
END;
END;
END
|
http://rosettacode.org/wiki/Polyspiral
|
Polyspiral
|
A Polyspiral is a spiral made of multiple line segments, whereby each segment is larger (or smaller) than the previous one by a given amount. Each segment also changes direction at a given angle.
Task
Animate a series of polyspirals, by drawing a complete spiral then incrementing the angle, and (after clearing the background) drawing the next, and so on. Every spiral will be a frame of the animation. The animation may stop as it goes full circle or continue indefinitely. The given input values may be varied.
If animation is not practical in your programming environment, you may show a single frame instead.
Pseudo code
set incr to 0.0
// animation loop
WHILE true
incr = (incr + 0.05) MOD 360
x = width / 2
y = height / 2
length = 5
angle = incr
// spiral loop
FOR 1 TO 150
drawline
change direction by angle
length = length + 3
angle = (angle + incr) MOD 360
ENDFOR
|
#C
|
C
|
#include<graphics.h>
#include<math.h>
#define factor M_PI/180
#define LAG 1000
void polySpiral(int windowWidth,int windowHeight){
int incr = 0, angle, i, length;
double x,y,x1,y1;
while(1){
incr = (incr + 5)%360;
x = windowWidth/2;
y = windowHeight/2;
length = 5;
angle = incr;
for(i=1;i<=150;i++){
x1 = x + length*cos(factor*angle);
y1 = y + length*sin(factor*angle);
line(x,y,x1,y1);
length += 3;
angle = (angle + incr)%360;
x = x1;
y = y1;
}
delay(LAG);
cleardevice();
}
}
int main()
{
initwindow(500,500,"Polyspiral");
polySpiral(500,500);
closegraph();
return 0;
}
|
http://rosettacode.org/wiki/Power_set
|
Power set
|
A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S.
Task
By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S.
For example, the power set of {1,2,3,4} is
{{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}.
For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set.
The power set of the empty set is the set which contains itself (20 = 1):
P
{\displaystyle {\mathcal {P}}}
(
∅
{\displaystyle \varnothing }
) = {
∅
{\displaystyle \varnothing }
}
And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2):
P
{\displaystyle {\mathcal {P}}}
({
∅
{\displaystyle \varnothing }
}) = {
∅
{\displaystyle \varnothing }
, {
∅
{\displaystyle \varnothing }
} }
Extra credit: Demonstrate that your language supports these last two powersets.
|
#11l
|
11l
|
F list_powerset(lst)
V result = [[Int]()]
L(x) lst
result.extend(result.map(subset -> subset [+] [@x]))
R result
print(list_powerset([1, 2, 3]))
|
http://rosettacode.org/wiki/Primality_by_trial_division
|
Primality by trial division
|
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
count in factors
prime decomposition
AKS test for primes
factors of an integer
Sieve of Eratosthenes
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#ABAP
|
ABAP
|
class ZMLA_ROSETTA definition
public
create public .
public section.
types:
enumber TYPE N LENGTH 60 .
types:
listof_enumber TYPE TABLE OF enumber .
class-methods IS_PRIME
importing
value(N) type ENUMBER
returning
value(OFLAG) type ABAP_BOOL .
class-methods IS_PRIME_I
importing
value(N) type I
returning
value(OFLAG) type ABAP_BOOL .
protected section.
private section.
ENDCLASS.
CLASS ZMLA_ROSETTA IMPLEMENTATION.
* <SIGNATURE>---------------------------------------------------------------------------------------+
* | Static Public Method ZMLA_ROSETTA=>IS_PRIME
* +-------------------------------------------------------------------------------------------------+
* | [--->] N TYPE ENUMBER
* | [<-()] OFLAG TYPE ABAP_BOOL
* +--------------------------------------------------------------------------------------</SIGNATURE>
method IS_PRIME.
IF n < 2.
oflag = abap_false.
RETURN.
ENDIF.
IF n = 2 or n = 3.
oflag = abap_true.
RETURN.
ENDIF.
IF n mod 2 = 0 or n mod 3 = 0.
oflag = abap_false.
RETURN.
ENDIF.
DATA: lim type enumber,
d type enumber,
i TYPE i VALUE 2.
lim = sqrt( n ).
d = 5.
WHILE d <= lim.
IF n mod d = 0.
oflag = abap_false.
RETURN.
ENDIF.
d = d + i.
i = 6 - i. " this modifies 2 into 4 and viceversa
ENDWHILE.
oflag = abap_true.
RETURN.
endmethod.
* <SIGNATURE>---------------------------------------------------------------------------------------+
* | Static Public Method ZMLA_ROSETTA=>IS_PRIME_I
* +-------------------------------------------------------------------------------------------------+
* | [--->] N TYPE I
* | [<-()] OFLAG TYPE ABAP_BOOL
* +--------------------------------------------------------------------------------------</SIGNATURE>
method IS_PRIME_I.
IF n < 2.
oflag = abap_false.
RETURN.
ENDIF.
IF n = 2 or n = 3.
oflag = abap_true.
RETURN.
ENDIF.
IF n mod 2 = 0 or n mod 3 = 0.
oflag = abap_false.
RETURN.
ENDIF.
DATA: lim type i,
d type i,
i TYPE i VALUE 2.
lim = sqrt( n ).
d = 5.
WHILE d <= lim.
IF n mod d = 0.
oflag = abap_false.
RETURN.
ENDIF.
d = d + i.
i = 6 - i. " this modifies 2 into 4 and viceversa
ENDWHILE.
oflag = abap_true.
RETURN.
endmethod.
ENDCLASS.
|
http://rosettacode.org/wiki/Price_fraction
|
Price fraction
|
A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 and 1.00, rescale according to the following table:
>= 0.00 < 0.06 := 0.10
>= 0.06 < 0.11 := 0.18
>= 0.11 < 0.16 := 0.26
>= 0.16 < 0.21 := 0.32
>= 0.21 < 0.26 := 0.38
>= 0.26 < 0.31 := 0.44
>= 0.31 < 0.36 := 0.50
>= 0.36 < 0.41 := 0.54
>= 0.41 < 0.46 := 0.58
>= 0.46 < 0.51 := 0.62
>= 0.51 < 0.56 := 0.66
>= 0.56 < 0.61 := 0.70
>= 0.61 < 0.66 := 0.74
>= 0.66 < 0.71 := 0.78
>= 0.71 < 0.76 := 0.82
>= 0.76 < 0.81 := 0.86
>= 0.81 < 0.86 := 0.90
>= 0.86 < 0.91 := 0.94
>= 0.91 < 0.96 := 0.98
>= 0.96 < 1.01 := 1.00
|
#Arturo
|
Arturo
|
pricePoints: [
0.06 0.10 0.11 0.18 0.16 0.26 0.21 0.32
0.26 0.38 0.31 0.44 0.36 0.50 0.41 0.54
0.46 0.58 0.51 0.62 0.56 0.66 0.61 0.70
0.66 0.74 0.71 0.78 0.76 0.82 0.81 0.86
0.86 0.90 0.91 0.94 0.96 0.98 1.01 1.00
]
getPricePoint: function [price][
loop pricePoints [limit,correct][
if price < limit -> return correct
]
]
tests: [0.3793 0.4425 0.0746 0.6918 0.2993 0.5486 0.7849 0.9383 0.2292]
loop tests 'test [
print [test "=>" getPricePoint test]
]
|
http://rosettacode.org/wiki/Proper_divisors
|
Proper divisors
|
The proper divisors of a positive integer N are those numbers, other than N itself, that divide N without remainder.
For N > 1 they will always include 1, but for N == 1 there are no proper divisors.
Examples
The proper divisors of 6 are 1, 2, and 3.
The proper divisors of 100 are 1, 2, 4, 5, 10, 20, 25, and 50.
Task
Create a routine to generate all the proper divisors of a number.
use it to show the proper divisors of the numbers 1 to 10 inclusive.
Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has.
Show all output here.
Related tasks
Amicable pairs
Abundant, deficient and perfect number classifications
Aliquot sequence classifications
Factors of an integer
Prime decomposition
|
#D
|
D
|
void main() /*@safe*/ {
import std.stdio, std.algorithm, std.range, std.typecons;
immutable properDivs = (in uint n) pure nothrow @safe /*@nogc*/ =>
iota(1, (n + 1) / 2 + 1).filter!(x => n % x == 0 && n != x);
iota(1, 11).map!properDivs.writeln;
iota(1, 20_001).map!(n => tuple(properDivs(n).count, n)).reduce!max.writeln;
}
|
http://rosettacode.org/wiki/Probabilistic_choice
|
Probabilistic choice
|
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is involved, this is subject to rounding errors).
aleph 1/5.0
beth 1/6.0
gimel 1/7.0
daleth 1/8.0
he 1/9.0
waw 1/10.0
zayin 1/11.0
heth 1759/27720 # adjusted so that probabilities add to 1
Related task
Random number generator (device)
|
#Factor
|
Factor
|
USING: arrays assocs combinators.random io kernel macros math
math.statistics prettyprint quotations sequences sorting formatting ;
IN: rosettacode.proba
CONSTANT: data
{
{ "aleph" 1/5.0 }
{ "beth" 1/6.0 }
{ "gimel" 1/7.0 }
{ "daleth" 1/8.0 }
{ "he" 1/9.0 }
{ "waw" 1/10.0 }
{ "zayin" 1/11.0 }
{ "heth" f }
}
MACRO: case-probas ( data -- case-probas )
[ first2 [ swap 1quotation 2array ] [ 1quotation ] if* ] map 1quotation ;
: expected ( name data -- float )
2dup at [ 2nip ] [ nip values sift sum 1 swap - ] if* ;
: generate ( # case-probas -- seq )
H{ } clone
[ [ [ casep ] [ inc-at ] bi* ] 2curry times ] keep ; inline
: normalize ( seq # -- seq )
[ clone ] dip [ /f ] curry assoc-map ;
: summarize1 ( name value data -- )
[ over ] dip expected
"%6s: %10f %10f\n" printf ;
: summarize ( generated data -- )
"Key" "Value" "expected" "%6s %10s %10s\n" printf
[ summarize1 ] curry assoc-each ;
: generate-normalized ( # proba -- seq )
[ generate ] [ drop normalize ] 2bi ; inline
: example ( # data -- )
[ case-probas generate-normalized ]
[ summarize ] bi ; inline
|
http://rosettacode.org/wiki/Probabilistic_choice
|
Probabilistic choice
|
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is involved, this is subject to rounding errors).
aleph 1/5.0
beth 1/6.0
gimel 1/7.0
daleth 1/8.0
he 1/9.0
waw 1/10.0
zayin 1/11.0
heth 1759/27720 # adjusted so that probabilities add to 1
Related task
Random number generator (device)
|
#Fermat
|
Fermat
|
trials:=1000000;
Array probs[8]; {store the probabilities}
[probs]:=[<i=1,8> 1/(i+4)];
probs[8]:=1-Sigma<i=1,7>[probs[i,1]];
Func Round( a, b ) = (2*a+b)\(2*b).; {rounds a fraction with numerator a and denominator b}
; {to the nearest integer (positive fractions only)}
Func Sel = {select a number from 1 to 8 according to the}
r:=Rand|27720; {specified probabilities}
if r < probs[1]*27720 then Return(1) fi;
if r < Sigma<i=1,2>[probs[i]]*27720 then Return(2) fi;
if r < Sigma<i=1,3>[probs[i]]*27720 then Return(3) fi;
if r < Sigma<i=1,4>[probs[i]]*27720 then Return(4) fi;
if r < Sigma<i=1,5>[probs[i]]*27720 then Return(5) fi;
if r < Sigma<i=1,6>[probs[i]]*27720 then Return(6) fi;
if r < Sigma<i=1,7>[probs[i]]*27720 then Return(7) fi;
Return(8);
.;
Array label[10]; {strings are not Fermat's strong suit}
Func Letter(n) = {assign a Hebrew letter to the numbers 1-8}
[label]:='heth ';
if n = 1 then [label]:='aleph ' fi;
if n = 2 then [label]:='beth ' fi;
if n = 3 then [label]:='gimel ' fi;
if n = 4 then [label]:='daleth ' fi;
if n = 5 then [label]:='he ' fi;
if n = 6 then [label]:='waw ' fi;
if n = 7 then [label]:='zayin ' fi;
.;
Array count[8]; {pick a bunch of random numbers}
for i = 1 to trials do
s:=Sel;
count[s]:=count[s]+1;
od;
for i = 1 to 8 do {now display some diagnostics}
Letter(i);
ctp:=count[i]/trials-probs[i];
!([label:char, count[i]/trials,' differs from ',probs[i]);
!(' by ',ctp, ' or about one part in ', Round(Denom(ctp),|Numer(ctp)|));
!!;
od;
!!('The various probabilities add up to ',Sigma<i=1,8>[count[i]/trials]); {check if our trials add to 1}
|
http://rosettacode.org/wiki/Primes_-_allocate_descendants_to_their_ancestors
|
Primes - allocate descendants to their ancestors
|
The concept, is to add the decomposition into prime factors of a number to get its 'ancestors'.
The objective is to demonstrate that the choice of the algorithm can be crucial in term of performance.
This solution could be compared to the solution that would use the decomposition into primes for all the numbers between 1 and 333.
The problem is to list, for a delimited set of ancestors (from 1 to 99) :
- the total of their own ancestors (LEVEL),
- their own ancestors (ANCESTORS),
- the total of the direct descendants (DESCENDANTS),
- all the direct descendants.
You only have to consider the prime factors < 100.
A grand total of the descendants has to be printed at the end of the list.
The task should be accomplished in a reasonable time-frame.
Example :
46 = 2*23 --> 2+23 = 25, is the parent of 46.
25 = 5*5 --> 5+5 = 10, is the parent of 25.
10 = 2*5 --> 2+5 = 7, is the parent of 10.
7 is a prime factor and, as such, has no parent.
46 has 3 ancestors (7, 10 and 25).
46 has 557 descendants.
The list layout and the output for Parent [46] :
[46] Level: 3
Ancestors: 7, 10, 25
Descendants: 557
129, 205, 246, 493, 518, 529, 740, 806, 888, 999, 1364, 1508, 1748, 2552, 2871, 3128, 3255, 3472, 3519, 3875, 3906, 4263, 4650, 4960, 5075, 5415, 5580, 5776, 5952, 6090, 6279, 6496, 6498, 6696, 6783, 7250, 7308, 7475, 7533, 8075, 8151, 8619, 8700, 8855, 8970, 9280, 9568, 9690, 10115, 10336, 10440, 10626, 10764, 11136, 11495, 11628, 11745, 12103, 12138, 12155, 12528, 12650, 13794, 14094, 14399, 14450, 14586, 15180, 15379, 15778, 16192, 17290, 17303, 17340, 18216, 18496, 20482, 20493, 20570, 20748, 20808, 21658, 21970, 22540, 23409, 24684, 24700, 26026, 26364, 27048, 29260, 29282, 29640, 30429, 30940, 31616, 32200, 33345, 35112, 35568, 36225, 36652, 37128, 37180, 38640, 39501, 40014, 41216, 41769, 41800, 43125, 43470, 44044, 44200, 44616, 46000, 46368, 47025, 49725, 50160, 50193, 51750, 52136, 52164, 52360, 53040, 53504, 55200, 56430, 56576, 58653, 58880, 58905, 59670, 60192, 62100, 62832, 62920, 63648, 66240, 66248, 67716, 69825, 70125, 70656, 70686, 70785, 71604, 74480, 74520, 74529, 74536, 74800, 75504, 79488, 83125, 83790, 83835, 83853, 84150, 84942, 87465, 88725, 89376, 89424, 89760, 93296, 94640, 95744, 99750, 99825, 100548, 100602, 100980, 104125, 104958, 105105, 105625, 106400, 106470, 106480, 107712, 112112, 113568, 118750, 119700, 119790, 121176, 124509, 124950, 125125, 126126, 126750, 127680, 127764, 127776, 133280, 135200, 136192, 136323, 142500, 143640, 143748, 148225, 148750, 149940, 150150, 152000, 152100, 153216, 156065, 159936, 160160, 161595, 162240, 171000, 172368, 173056, 177870, 178500, 178750, 179928, 180180, 182400, 182520, 184877, 187278, 189728, 190400, 192192, 192375, 193914, 194560, 194688, 202419, 205200, 205335, 211750, 212500, 213444, 214200, 214500, 216216, 218880, 219024, 222950, 228480, 228800, 230850, 233472, 240975, 243243, 243712, 246240, 246402, 254100, 255000, 257040, 257400, 262656, 264110, 267540, 271040, 272000, 274176, 274560, 277020, 285376, 286875, 289170, 289575, 292864, 295488, 302500, 304920, 306000, 308448, 308880, 316932, 318500, 321048, 325248, 326400, 329472, 332424, 343035, 344250, 347004, 347490, 348160, 361179, 363000, 365904, 367200, 370656, 373977, 377300, 382200, 387200, 391680, 407680, 408375, 411642, 413100, 416988, 417792, 429975, 435600, 440640, 452760, 455000, 458640, 464640, 470016, 470596, 482944, 489216, 490050, 495616, 495720, 509355, 511875, 515970, 522720, 528768, 539000, 543312, 546000, 550368, 557568, 557685, 582400, 588060, 594864, 606375, 609375, 611226, 614250, 619164, 627264, 646800, 650000, 655200, 669222, 672280, 689920, 698880, 705672, 721875, 727650, 731250, 737100, 745472, 756315, 770000, 776160, 780000, 786240, 793881, 806736, 827904, 832000, 838656, 859375, 866250, 873180, 877500, 884520, 900375, 907578, 924000, 931392, 936000, 943488, 960400, 985600, 995085, 998400, 1031250, 1039500, 1047816, 1053000, 1061424, 1064960, 1071875, 1080450, 1100000, 1108800, 1123200, 1152480, 1178793, 1182720, 1184625, 1194102, 1198080, 1229312, 1237500, 1247400, 1261568, 1263600, 1277952, 1286250, 1296540, 1320000, 1330560, 1347840, 1372000, 1382976, 1403325, 1408000, 1419264, 1421550, 1437696, 1485000, 1496880, 1516320, 1531250, 1543500, 1555848, 1584000, 1596672, 1617408, 1646400, 1670625, 1683990, 1689600, 1705860, 1750329, 1756160, 1782000, 1796256, 1802240, 1819584, 1837500, 1852200, 1900800, 1960000, 1975680, 2004750, 2020788, 2027520, 2047032, 2083725, 2107392, 2138400, 2162688, 2187500, 2205000, 2222640, 2280960, 2302911, 2352000, 2370816, 2405700, 2433024, 2480625, 2500470, 2508800, 2566080, 2625000, 2646000, 2667168, 2737152, 2800000, 2822400, 2886840, 2953125, 2976750, 3000564, 3010560, 3079296, 3125000, 3150000, 3175200, 3211264, 3247695, 3360000, 3386880, 3464208, 3515625, 3543750, 3572100, 3584000, 3612672, 3750000, 3780000, 3810240, 3897234, 4000000, 4032000, 4064256, 4218750, 4252500, 4286520, 4300800, 4500000, 4536000, 4572288, 4587520, 4800000, 4822335, 4838400, 5062500, 5103000, 5120000, 5143824, 5160960, 5400000, 5443200, 5505024, 5740875, 5760000, 5786802, 5806080, 6075000, 6123600, 6144000, 6193152, 6480000, 6531840, 6553600, 6834375, 6889050, 6912000, 6967296, 7290000, 7348320, 7372800, 7776000, 7838208, 7864320, 8201250, 8266860, 8294400, 8388608, 8748000, 8817984, 8847360, 9331200, 9437184, 9841500, 9920232, 9953280, 10497600, 10616832, 11160261, 11197440, 11809800, 11943936, 12597120, 13286025, 13436928, 14171760, 15116544, 15943230, 17006112, 19131876
Some figures :
The biggest descendant number : 3^33 = 5.559.060.566.555.523 (parent 99)
Total Descendants 546.986
|
#Simula
|
Simula
|
COMMENT cim --memory-pool-size=512 allocate-descendants-to-their-ancestors.sim ;
BEGIN
COMMENT ABSTRACT FRAMEWORK CLASSES ;
CLASS ITEM;
BEGIN
END ITEM;
CLASS ITEMLIST;
BEGIN
CLASS ITEMARRAY(N); INTEGER N;
BEGIN REF(ITEM) ARRAY DATA(0:N-1);
END ITEMARRAY;
PROCEDURE EXPAND(N); INTEGER N;
BEGIN
INTEGER I;
REF(ITEMARRAY) TEMP;
TEMP :- NEW ITEMARRAY(N);
FOR I := 0 STEP 1 UNTIL SIZE-1 DO
TEMP.DATA(I) :- ITEMS.DATA(I);
ITEMS :- TEMP;
END EXPAND;
PROCEDURE APPEND(RI); REF(ITEM) RI;
BEGIN
IF SIZE + 1 > CAPACITY THEN
BEGIN
CAPACITY := 2 * CAPACITY;
EXPAND(CAPACITY);
END;
ITEMS.DATA(SIZE) :- RI;
SIZE := SIZE + 1;
END APPEND;
PROCEDURE APPENDALL(IL); REF(ITEMLIST) IL;
BEGIN
INTEGER I;
FOR I := 0 STEP 1 UNTIL IL.SIZE-1 DO
APPEND(IL.ELEMENT(I));
END APPENDALL;
REF(ITEM) PROCEDURE ELEMENT(I); INTEGER I;
BEGIN
IF I < 0 OR I > SIZE-1 THEN ERROR("ELEMENT: INDEX OUT OF BOUNDS");
ELEMENT :- ITEMS.DATA(I);
END ELEMENT;
REF(ITEM) PROCEDURE SETELEMENT(I, IT); INTEGER I; REF(ITEM) IT;
BEGIN
IF I < 0 OR I > SIZE-1 THEN ERROR("SETELEMENT: INDEX OUT OF BOUNDS");
ITEMS.DATA(I) :- IT;
END SETELEMENT;
REF(ITEM) PROCEDURE POP;
BEGIN
REF(ITEM) RESULT;
IF SIZE=0 THEN ERROR("POP: EMPTY ITEMLIST");
RESULT :- ITEMS.DATA(SIZE-1);
ITEMS.DATA(SIZE-1) :- NONE;
SIZE := SIZE-1;
POP :- RESULT;
END POP;
PROCEDURE SORT(COMPARE_PROC);
PROCEDURE COMPARE_PROC IS
INTEGER PROCEDURE COMPARE_PROC(IT1,IT2); REF(ITEM) IT1,IT2;;
BEGIN
PROCEDURE SWAP(I,J); INTEGER I,J;
BEGIN
REF(ITEM) T;
T :- ITEMS.DATA(I);
ITEMS.DATA(I) :- ITEMS.DATA(J);
ITEMS.DATA(J) :- T;
END SWAP;
PROCEDURE QUICKSORT(L,R); INTEGER L,R;
BEGIN
REF(ITEM) PIVOT;
INTEGER I, J;
PIVOT :- ITEMS.DATA((L+R)//2); I := L; J := R;
WHILE I <= J DO
BEGIN
WHILE COMPARE_PROC(ITEMS.DATA(I), PIVOT) < 0 DO I := I+1;
WHILE COMPARE_PROC(PIVOT, ITEMS.DATA(J)) < 0 DO J := J-1;
IF I <= J THEN
BEGIN SWAP(I,J); I := I+1; J := J-1;
END;
END;
IF L < J THEN QUICKSORT(L, J);
IF I < R THEN QUICKSORT(I, R);
END QUICKSORT;
IF SIZE >= 2 THEN
QUICKSORT(0,SIZE-1);
END SORT;
INTEGER CAPACITY;
INTEGER SIZE;
REF(ITEMARRAY) ITEMS;
CAPACITY := 20;
SIZE := 0;
EXPAND(CAPACITY);
END ITEMLIST;
COMMENT PROBLEM SPECIFIC PART ;
ITEM CLASS REALITEM(X); LONG REAL X;
BEGIN
END REALITEM;
ITEMLIST CLASS LIST_OF_REAL;
BEGIN
LONG REAL PROCEDURE ELEMENT(I); INTEGER I;
ELEMENT := ITEMS.DATA(I) QUA REALITEM.X;
PROCEDURE APPEND(X); LONG REAL X;
THIS ITEMLIST.APPEND(NEW REALITEM(X));
PROCEDURE SORT;
BEGIN
INTEGER PROCEDURE CMP(IT1,IT2); REF(ITEM) IT1,IT2;
CMP := IF IT1 QUA REALITEM.X < IT2 QUA REALITEM.X THEN -1 ELSE
IF IT1 QUA REALITEM.X > IT2 QUA REALITEM.X THEN +1 ELSE 0;
THIS ITEMLIST.SORT(CMP);
END SORT;
PROCEDURE OUTLIST;
BEGIN
INTEGER I;
TEXT FMT;
OUTTEXT("[");
FMT :- BLANKS(20);
FOR I := 0 STEP 1 UNTIL SIZE-1 DO
BEGIN
IF I < 3 OR I > SIZE-1-3 THEN BEGIN
IF I > 0 THEN OUTTEXT(", ");
FMT.PUTFIX(ELEMENT(I), 0);
FMT.SETPOS(1);
WHILE FMT.MORE DO
BEGIN
CHARACTER C;
C := FMT.GETCHAR;
IF C <> ' ' THEN OUTCHAR(C);
END
END ELSE BEGIN OUTTEXT(", ..."); I := SIZE-1-3; END;
END;
OUTTEXT("]");
END OUTLIST;
END LIST_OF_REAL;
ITEM CLASS REALLISTITEM(LRL); REF(LIST_OF_REAL) LRL;
BEGIN
END REALLISTITEM;
ITEMLIST CLASS LIST_OF_REALLIST;
BEGIN
REF(LIST_OF_REAL) PROCEDURE ELEMENT(I); INTEGER I;
ELEMENT :- ITEMS.DATA(I) QUA REALLISTITEM.LRL;
PROCEDURE APPEND(LRL); REF(LIST_OF_REAL) LRL;
THIS ITEMLIST.APPEND(NEW REALLISTITEM(LRL));
PROCEDURE OUTLIST;
BEGIN
INTEGER I;
OUTTEXT("[");
FOR I := 0 STEP 1 UNTIL SIZE-1 DO
BEGIN
IF I > 0 THEN OUTTEXT(", ");
ELEMENT(I).OUTLIST;
END;
OUTTEXT("]");
END OUTLIST;
END LIST_OF_REALLIST;
REF(LIST_OF_REAL) PROCEDURE GET_PRIMES(MAX);
INTEGER MAX;
BEGIN
REF(LIST_OF_REAL) LPRIMES;
LPRIMES :- NEW LIST_OF_REAL;
IF MAX < 2 THEN
GOTO RETURN
ELSE
BEGIN
INTEGER X;
LPRIMES.APPEND(2);
FOR X := 3 STEP 2 UNTIL MAX DO BEGIN
INTEGER I;
LONG REAL P;
FOR I := 0 STEP 1 UNTIL LPRIMES.SIZE-1 DO BEGIN
P := LPRIMES.ELEMENT(I);
IF (X / P) = ENTIER(X / P) THEN GOTO BREAK;
END;
LPRIMES.APPEND(X);
BREAK:
END;
END;
RETURN:
GET_PRIMES :- LPRIMES;
END GET_PRIMES;
INTEGER MAXSUM, I, S, PRI, TOTAL, DI;
REF(LIST_OF_REALLIST) DESCENDANTS, ANCESTORS;
REF(LIST_OF_REAL) PRIMES, LR, LRS;
LONG REAL P, D, PR;
BOOLEAN TAKEWHILE;
MAXSUM := 99;
DESCENDANTS :- NEW LIST_OF_REALLIST;
ANCESTORS :- NEW LIST_OF_REALLIST;
FOR I := 0 STEP 1 UNTIL MAXSUM DO BEGIN
DESCENDANTS.APPEND(NEW LIST_OF_REAL);
ANCESTORS .APPEND(NEW LIST_OF_REAL);
END;
PRIMES :- GET_PRIMES(MAXSUM);
FOR I := 0 STEP 1 UNTIL PRIMES.SIZE-1 DO
BEGIN
P := PRIMES.ELEMENT(I);
DESCENDANTS.ELEMENT(P).APPEND(P);
FOR S := 1 STEP 1 UNTIL DESCENDANTS.SIZE-P-1 DO
BEGIN
LRS :- DESCENDANTS.ELEMENT(S);
FOR PRI := 0 STEP 1 UNTIL LRS.SIZE-1 DO
BEGIN
PR := LRS.ELEMENT(PRI);
DESCENDANTS.ELEMENT(S + P).APPEND(P * PR);
END;
END;
END;
FOR I := 0 STEP 1 UNTIL PRIMES.SIZE-1 DO
BEGIN
P := PRIMES.ELEMENT(I);
DESCENDANTS.ELEMENT(P).POP;
END;
DESCENDANTS.ELEMENT(4).POP;
TOTAL := 0;
FOR S := 1 STEP 1 UNTIL MAXSUM DO
BEGIN
LRS :- DESCENDANTS.ELEMENT(S);
LRS.SORT;
FOR DI := 0 STEP 1 UNTIL LRS.SIZE-1 DO
BEGIN
D := LRS.ELEMENT(DI);
IF D <= MAXSUM THEN
BEGIN
REF(LIST_OF_REAL) ANCD;
ANCD :- NEW LIST_OF_REAL;
ANCD.APPENDALL(ANCESTORS.ELEMENT(S));
ANCD.APPEND(S);
ANCESTORS.SETELEMENT(D, NEW REALLISTITEM(ANCD));
END
ELSE GOTO BREAK;
END;
BREAK:
OUTTEXT("[");
OUTINT(S, 0);
OUTTEXT("] LEVEL: ");
OUTINT(ANCESTORS.ELEMENT(S).SIZE, 0);
OUTIMAGE;
OUTTEXT("ANCESTORS: ");
ANCESTORS.ELEMENT(S).OUTLIST;
OUTIMAGE;
OUTTEXT("DESCENDANTS: ");
OUTINT(LRS.SIZE,0);
OUTIMAGE;
LRS.OUTLIST;
OUTIMAGE;
OUTIMAGE;
TOTAL := TOTAL + LRS.SIZE;
END;
OUTTEXT("TOTAL DESCENDANTS ");
OUTINT(TOTAL, 0);
OUTIMAGE;
END.
|
http://rosettacode.org/wiki/Primes_-_allocate_descendants_to_their_ancestors
|
Primes - allocate descendants to their ancestors
|
The concept, is to add the decomposition into prime factors of a number to get its 'ancestors'.
The objective is to demonstrate that the choice of the algorithm can be crucial in term of performance.
This solution could be compared to the solution that would use the decomposition into primes for all the numbers between 1 and 333.
The problem is to list, for a delimited set of ancestors (from 1 to 99) :
- the total of their own ancestors (LEVEL),
- their own ancestors (ANCESTORS),
- the total of the direct descendants (DESCENDANTS),
- all the direct descendants.
You only have to consider the prime factors < 100.
A grand total of the descendants has to be printed at the end of the list.
The task should be accomplished in a reasonable time-frame.
Example :
46 = 2*23 --> 2+23 = 25, is the parent of 46.
25 = 5*5 --> 5+5 = 10, is the parent of 25.
10 = 2*5 --> 2+5 = 7, is the parent of 10.
7 is a prime factor and, as such, has no parent.
46 has 3 ancestors (7, 10 and 25).
46 has 557 descendants.
The list layout and the output for Parent [46] :
[46] Level: 3
Ancestors: 7, 10, 25
Descendants: 557
129, 205, 246, 493, 518, 529, 740, 806, 888, 999, 1364, 1508, 1748, 2552, 2871, 3128, 3255, 3472, 3519, 3875, 3906, 4263, 4650, 4960, 5075, 5415, 5580, 5776, 5952, 6090, 6279, 6496, 6498, 6696, 6783, 7250, 7308, 7475, 7533, 8075, 8151, 8619, 8700, 8855, 8970, 9280, 9568, 9690, 10115, 10336, 10440, 10626, 10764, 11136, 11495, 11628, 11745, 12103, 12138, 12155, 12528, 12650, 13794, 14094, 14399, 14450, 14586, 15180, 15379, 15778, 16192, 17290, 17303, 17340, 18216, 18496, 20482, 20493, 20570, 20748, 20808, 21658, 21970, 22540, 23409, 24684, 24700, 26026, 26364, 27048, 29260, 29282, 29640, 30429, 30940, 31616, 32200, 33345, 35112, 35568, 36225, 36652, 37128, 37180, 38640, 39501, 40014, 41216, 41769, 41800, 43125, 43470, 44044, 44200, 44616, 46000, 46368, 47025, 49725, 50160, 50193, 51750, 52136, 52164, 52360, 53040, 53504, 55200, 56430, 56576, 58653, 58880, 58905, 59670, 60192, 62100, 62832, 62920, 63648, 66240, 66248, 67716, 69825, 70125, 70656, 70686, 70785, 71604, 74480, 74520, 74529, 74536, 74800, 75504, 79488, 83125, 83790, 83835, 83853, 84150, 84942, 87465, 88725, 89376, 89424, 89760, 93296, 94640, 95744, 99750, 99825, 100548, 100602, 100980, 104125, 104958, 105105, 105625, 106400, 106470, 106480, 107712, 112112, 113568, 118750, 119700, 119790, 121176, 124509, 124950, 125125, 126126, 126750, 127680, 127764, 127776, 133280, 135200, 136192, 136323, 142500, 143640, 143748, 148225, 148750, 149940, 150150, 152000, 152100, 153216, 156065, 159936, 160160, 161595, 162240, 171000, 172368, 173056, 177870, 178500, 178750, 179928, 180180, 182400, 182520, 184877, 187278, 189728, 190400, 192192, 192375, 193914, 194560, 194688, 202419, 205200, 205335, 211750, 212500, 213444, 214200, 214500, 216216, 218880, 219024, 222950, 228480, 228800, 230850, 233472, 240975, 243243, 243712, 246240, 246402, 254100, 255000, 257040, 257400, 262656, 264110, 267540, 271040, 272000, 274176, 274560, 277020, 285376, 286875, 289170, 289575, 292864, 295488, 302500, 304920, 306000, 308448, 308880, 316932, 318500, 321048, 325248, 326400, 329472, 332424, 343035, 344250, 347004, 347490, 348160, 361179, 363000, 365904, 367200, 370656, 373977, 377300, 382200, 387200, 391680, 407680, 408375, 411642, 413100, 416988, 417792, 429975, 435600, 440640, 452760, 455000, 458640, 464640, 470016, 470596, 482944, 489216, 490050, 495616, 495720, 509355, 511875, 515970, 522720, 528768, 539000, 543312, 546000, 550368, 557568, 557685, 582400, 588060, 594864, 606375, 609375, 611226, 614250, 619164, 627264, 646800, 650000, 655200, 669222, 672280, 689920, 698880, 705672, 721875, 727650, 731250, 737100, 745472, 756315, 770000, 776160, 780000, 786240, 793881, 806736, 827904, 832000, 838656, 859375, 866250, 873180, 877500, 884520, 900375, 907578, 924000, 931392, 936000, 943488, 960400, 985600, 995085, 998400, 1031250, 1039500, 1047816, 1053000, 1061424, 1064960, 1071875, 1080450, 1100000, 1108800, 1123200, 1152480, 1178793, 1182720, 1184625, 1194102, 1198080, 1229312, 1237500, 1247400, 1261568, 1263600, 1277952, 1286250, 1296540, 1320000, 1330560, 1347840, 1372000, 1382976, 1403325, 1408000, 1419264, 1421550, 1437696, 1485000, 1496880, 1516320, 1531250, 1543500, 1555848, 1584000, 1596672, 1617408, 1646400, 1670625, 1683990, 1689600, 1705860, 1750329, 1756160, 1782000, 1796256, 1802240, 1819584, 1837500, 1852200, 1900800, 1960000, 1975680, 2004750, 2020788, 2027520, 2047032, 2083725, 2107392, 2138400, 2162688, 2187500, 2205000, 2222640, 2280960, 2302911, 2352000, 2370816, 2405700, 2433024, 2480625, 2500470, 2508800, 2566080, 2625000, 2646000, 2667168, 2737152, 2800000, 2822400, 2886840, 2953125, 2976750, 3000564, 3010560, 3079296, 3125000, 3150000, 3175200, 3211264, 3247695, 3360000, 3386880, 3464208, 3515625, 3543750, 3572100, 3584000, 3612672, 3750000, 3780000, 3810240, 3897234, 4000000, 4032000, 4064256, 4218750, 4252500, 4286520, 4300800, 4500000, 4536000, 4572288, 4587520, 4800000, 4822335, 4838400, 5062500, 5103000, 5120000, 5143824, 5160960, 5400000, 5443200, 5505024, 5740875, 5760000, 5786802, 5806080, 6075000, 6123600, 6144000, 6193152, 6480000, 6531840, 6553600, 6834375, 6889050, 6912000, 6967296, 7290000, 7348320, 7372800, 7776000, 7838208, 7864320, 8201250, 8266860, 8294400, 8388608, 8748000, 8817984, 8847360, 9331200, 9437184, 9841500, 9920232, 9953280, 10497600, 10616832, 11160261, 11197440, 11809800, 11943936, 12597120, 13286025, 13436928, 14171760, 15116544, 15943230, 17006112, 19131876
Some figures :
The biggest descendant number : 3^33 = 5.559.060.566.555.523 (parent 99)
Total Descendants 546.986
|
#Visual_Basic_.NET
|
Visual Basic .NET
|
Imports System.Math
Module Module1
Const MAXPRIME = 99 ' upper bound for the prime factors
Const MAXPARENT = 99 ' greatest parent number
Const NBRCHILDREN = 547100 ' max number of children (total descendants)
Public Primes As New Collection() ' table of the prime factors
Public PrimesR As New Collection() ' table of the prime factors in reversed order
Public Ancestors As New Collection() ' table of the parent's ancestors
Public Parents(MAXPARENT + 1) As Integer ' index table of the root descendant (per parent)
Public CptDescendants(MAXPARENT + 1) As Integer ' counter table of the descendants (per parent)
Public Children(NBRCHILDREN) As ChildStruct ' table of the whole descendants
Public iChildren As Integer ' max index of the Children table
Public Delimiter As String = ", "
Public Structure ChildStruct
Public Child As Long
Public pLower As Integer
Public pHigher As Integer
End Structure
Sub Main()
Dim Parent As Short
Dim Sum As Short
Dim i As Short
Dim TotDesc As Integer = 0
Dim MidPrime As Integer
If GetPrimes(Primes, MAXPRIME) = vbFalse Then
Return
End If
For i = Primes.Count To 1 Step -1
PrimesR.Add(Primes.Item(i))
Next
MidPrime = PrimesR.Item(1) / 2
For Each Prime In PrimesR
Parents(Prime) = InsertChild(Parents(Prime), Prime)
CptDescendants(Prime) += 1
If Prime > MidPrime Then
Continue For
End If
For Parent = 1 To MAXPARENT
Sum = Parent + Prime
If Sum > MAXPARENT Then
Exit For
End If
If Parents(Parent) Then
InsertPreorder(Parents(Parent), Sum, Prime)
CptDescendants(Sum) += CptDescendants(Parent)
End If
Next
Next
RemoveFalseChildren()
If MAXPARENT > MAXPRIME Then
If GetPrimes(Primes, MAXPARENT) = vbFalse Then
Return
End If
End If
FileOpen(1, "Ancestors.txt", OpenMode.Output)
For Parent = 1 To MAXPARENT
GetAncestors(Parent)
PrintLine(1, "[" & Parent.ToString & "] Level: " & Ancestors.Count.ToString)
If Ancestors.Count Then
Print(1, "Ancestors: " & Ancestors.Item(1).ToString)
For i = 2 To Ancestors.Count
Print(1, ", " & Ancestors.Item(i).ToString)
Next
PrintLine(1)
Ancestors.Clear()
Else
PrintLine(1, "Ancestors: None")
End If
If CptDescendants(Parent) Then
PrintLine(1, "Descendants: " & CptDescendants(Parent).ToString)
Delimiter = ""
PrintDescendants(Parents(Parent))
PrintLine(1)
TotDesc += CptDescendants(Parent)
Else
PrintLine(1, "Descendants: None")
End If
PrintLine(1)
Next
Primes.Clear()
PrimesR.Clear()
PrintLine(1, "Total descendants " & TotDesc.ToString)
PrintLine(1)
FileClose(1)
End Sub
Function InsertPreorder(_index As Integer, _sum As Short, _prime As Short)
Parents(_sum) = InsertChild(Parents(_sum), Children(_index).Child * _prime)
If Children(_index).pLower Then
InsertPreorder(Children(_index).pLower, _sum, _prime)
End If
If Children(_index).pHigher Then
InsertPreorder(Children(_index).pHigher, _sum, _prime)
End If
Return Nothing
End Function
Function InsertChild(_index As Integer, _child As Long) As Integer
If _index Then
If _child <= Children(_index).Child Then
Children(_index).pLower = InsertChild(Children(_index).pLower, _child)
Else
Children(_index).pHigher = InsertChild(Children(_index).pHigher, _child)
End If
Else
iChildren += 1
_index = iChildren
Children(_index).Child = _child
Children(_index).pLower = 0
Children(_index).pHigher = 0
End If
Return _index
End Function
Function RemoveFalseChildren()
Dim Exclusions As New Collection
Exclusions.Add(4)
For Each Prime In Primes
Exclusions.Add(Prime)
Next
For Each ex In Exclusions
Parents(ex) = Children(Parents(ex)).pHigher
CptDescendants(ex) -= 1
Next
Exclusions.Clear()
Return Nothing
End Function
Function GetAncestors(_child As Short)
Dim Child As Short = _child
Dim Parent As Short = 0
For Each Prime In Primes
If Child = 1 Then
Exit For
End If
While Child Mod Prime = 0
Child /= Prime
Parent += Prime
End While
Next
If Parent = _child Or _child = 1 Then
Return Nothing
End If
GetAncestors(Parent)
Ancestors.Add(Parent)
Return Nothing
End Function
Function PrintDescendants(_index As Integer)
If Children(_index).pLower Then
PrintDescendants(Children(_index).pLower)
End If
Print(1, Delimiter.ToString & Children(_index).Child.ToString)
Delimiter = ", "
If Children(_index).pHigher Then
PrintDescendants(Children(_index).pHigher)
End If
Return Nothing
End Function
Function GetPrimes(ByRef _primes As Object, Optional _maxPrime As Integer = 2) As Boolean
Dim Value As Integer = 3
Dim Max As Integer
Dim Prime As Integer
If _maxPrime < 2 Then
Return vbFalse
End If
_primes.Add(2)
While Value <= _maxPrime
Max = Floor(Sqrt(Value))
For Each Prime In _primes
If Prime > Max Then
_primes.Add(Value)
Exit For
End If
If Value Mod Prime = 0 Then
Exit For
End If
Next
Value += 2
End While
Return vbTrue
End Function
End Module
|
http://rosettacode.org/wiki/Priority_queue
|
Priority queue
|
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order.
Task
Create a priority queue. The queue must support at least two operations:
Insertion. An element is added to the queue with a priority (a numeric value).
Top item removal. Deletes the element or one of the elements with the current top priority and return it.
Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc.
To test your implementation, insert a number of elements into the queue, each with some random priority.
Then dequeue them sequentially; now the elements should be sorted by priority.
You can use the following task/priority items as input data:
Priority Task
══════════ ════════════════
3 Clear drains
4 Feed cat
5 Make tea
1 Solve RC tasks
2 Tax return
The implementation should try to be efficient. A typical implementation has O(log n) insertion and extraction time, where n is the number of items in the queue.
You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc. If so, discuss the reasons behind it.
|
#EchoLisp
|
EchoLisp
|
(lib 'tree)
(define tasks (make-bin-tree 3 "Clear drains"))
(bin-tree-insert tasks 2 "Tax return")
(bin-tree-insert tasks 5 "Make tea")
(bin-tree-insert tasks 1 "Solve RC tasks")
(bin-tree-insert tasks 4 "Feed 🐡")
(bin-tree-pop-first tasks) → (1 . "Solve RC tasks")
(bin-tree-pop-first tasks) → (2 . "Tax return")
(bin-tree-pop-first tasks) → (3 . "Clear drains")
(bin-tree-pop-first tasks) → (4 . "Feed 🐡")
(bin-tree-pop-first tasks) → (5 . "Make tea")
(bin-tree-pop-first tasks) → null
;; similarly
(bin-tree-pop-last tasks) → (5 . "Make tea")
(bin-tree-pop-last tasks) → (4 . "Feed 🐡")
; etc.
|
http://rosettacode.org/wiki/Problem_of_Apollonius
|
Problem of Apollonius
|
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the example in the code are shown in the diagram (below and to the right).
The red circle is "internally tangent" to all three black circles, and the green circle is "externally tangent" to all three black circles.
|
#Lasso
|
Lasso
|
define solveApollonius(c1, c2, c3, s1, s2, s3) => {
local(
x1 = decimal(#c1->get(1)),
y1 = decimal(#c1->get(2)),
r1 = decimal(#c1->get(3))
)
local(
x2 = decimal(#c2->get(1)),
y2 = decimal(#c2->get(2)),
r2 = decimal(#c2->get(3))
)
local(
x3 = decimal(#c3->get(1)),
y3 = decimal(#c3->get(2)),
r3 = decimal(#c3->get(3))
)
local(
v11 = 2*#x2 - 2*#x1,
v12 = 2*#y2 - 2*#y1,
v13 = #x1*#x1 - #x2*#x2 + #y1*#y1 - #y2*#y2 - #r1*#r1 + #r2*#r2,
v14 = 2*#s2*#r2 - 2*#s1*#r1,
v21 = 2*#x3 - 2*#x2,
v22 = 2*#y3 - 2*#y2,
v23 = #x2*#x2 - #x3*#x3 + #y2*#y2 - #y3*#y3 - #r2*#r2 + #r3*#r3,
v24 = 2*#s3*#r3 - 2*#s2*#r2,
w12 = #v12/#v11,
w13 = #v13/#v11,
w14 = #v14/#v11,
w22 = #v22/#v21-#w12,
w23 = #v23/#v21-#w13,
w24 = #v24/#v21-#w14,
P = -#w23/#w22,
Q = #w24/#w22,
M = -#w12*#P-#w13,
N = #w14 - #w12*#Q,
a = #N*#N + #Q*#Q - 1,
b = 2*#M*#N - 2*#N*#x1 + 2*#P*#Q - 2*#Q*#y1 + 2*#s1*#r1,
c = #x1*#x1 + #M*#M - 2*#M*#x1 + #P*#P + #y1*#y1 - 2*#P*#y1 - #r1*#r1
)
// Find a root of a quadratic equation. This requires the circle centers not to be e.g. colinear
local(
D = #b*#b-4*#a*#c,
rs = (-#b - #D->sqrt)/(2*#a),
xs = #M+#N*#rs,
ys = #P+#Q*#rs
)
return (:#xs, #ys, #rs)
}
// Tests:
solveApollonius((:0, 0, 1), (:4, 0, 1), (:2, 4, 2), 1,1,1)
solveApollonius((:0, 0, 1), (:4, 0, 1), (:2, 4, 2), -1,-1,-1)
|
http://rosettacode.org/wiki/Problem_of_Apollonius
|
Problem of Apollonius
|
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the example in the code are shown in the diagram (below and to the right).
The red circle is "internally tangent" to all three black circles, and the green circle is "externally tangent" to all three black circles.
|
#Liberty_BASIC
|
Liberty BASIC
|
circle1$ =" 0.000, 0.000, 1.000"
circle2$ =" 4.000, 0.000, 1.000"
circle3$ =" 2.000, 4.000, 2.000"
print " x_pos y_pos radius"
print circle1$
print circle2$
print circle3$
print
print ApolloniusSolver$( circle1$, circle2$, circle3$, 1, 1, 1)
print ApolloniusSolver$( circle1$, circle2$, circle3$, -1, -1, -1)
end
function ApolloniusSolver$( c1$, c2$, c3$, s1, s2, s3)
x1 =val( word$( c1$, 1, ",")): y1 =val( word$( c1$, 2, ",")): r1 =val( word$( c1$, 3, ","))
x2 =val( word$( c2$, 1, ",")): y2 =val( word$( c2$, 2, ",")): r2 =val( word$( c2$, 3, ","))
x3 =val( word$( c3$, 1, ",")): y3 =val( word$( c3$, 2, ",")): r3 =val( word$( c3$, 3, ","))
v11 = 2 *x2 -2 *x1
v12 = 2 *y2 -2*y1
v13 = x1 *x1 - x2 *x2 + y1 *y1 - y2 *y2 -r1 *r1 +r2 *r2
v14 = 2 *s2 *r2 -2 *s1 *r1
v21 = 2 *x3 -2 *x2
v22 = 2 *y3 -2*y2
v23 = x2 *x2 -x3 *x3 + y2 *y2 -y3 *y3 -r2 *r2 +r3 *r3
v24 = 2 *s3 *r3 - 2 *s2 *r2
w12 = v12 /v11
w13 = v13 /v11
w14 = v14 /v11
w22 = v22 /v21 -w12
w23 = v23 /v21 -w13
w24 = v24 /v21 -w14
P = 0 -w23 /w22
Q = w24 /w22
M = 0 -w12 *P -w13
N = w14 -w12 *Q
a = N *N + Q *Q -1
b = 2 *M *N -2 *N *x1 + 2 *P *Q -2 *Q *y1 +2 *s1 *r1
c = x1 *x1 +M *M -2 *M *x1 +P *P +y1 *y1 -2 *P *y1 -r1 *r1
D = b *b -4 *a *c
Radius =( 0 -b -Sqr( D)) /( 2 *a)
XPos =M +N *Radius
YPos =P +Q *Radius
ApolloniusSolver$ =using( "###.###", XPos) +"," +using( "###.###", YPos) +using( "###.###", Radius)
end function
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#PicoLisp
|
PicoLisp
|
: (cmd)
-> "/usr/bin/picolisp"
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#PowerBASIC
|
PowerBASIC
|
#INCLUDE "Win32API.inc"
'[...]
DIM fullpath AS ASCIIZ * 260, appname AS STRING
GetModuleFileNameA 0, fullpath, 260
IF INSTR(fullpath, "\") THEN
appname = MID$(fullpath, INSTR(-1, fullpath, "\") + 1)
ELSE
appname = fullpath
END IF
|
http://rosettacode.org/wiki/Pythagorean_triples
|
Pythagorean triples
|
A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displaystyle a,b,c}
are co-prime, that is, if their pairwise greatest common divisors
g
c
d
(
a
,
b
)
=
g
c
d
(
a
,
c
)
=
g
c
d
(
b
,
c
)
=
1
{\displaystyle {\rm {gcd}}(a,b)={\rm {gcd}}(a,c)={\rm {gcd}}(b,c)=1}
.
Because of their relationship through the Pythagorean theorem, a, b, and c are co-prime if a and b are co-prime (
g
c
d
(
a
,
b
)
=
1
{\displaystyle {\rm {gcd}}(a,b)=1}
).
Each triple forms the length of the sides of a right triangle, whose perimeter is
P
=
a
+
b
+
c
{\displaystyle P=a+b+c}
.
Task
The task is to determine how many Pythagorean triples there are with a perimeter no larger than 100 and the number of these that are primitive.
Extra credit
Deal with large values. Can your program handle a maximum perimeter of 1,000,000? What about 10,000,000? 100,000,000?
Note: the extra credit is not for you to demonstrate how fast your language is compared to others; you need a proper algorithm to solve them in a timely manner.
Related tasks
Euler's sum of powers conjecture
List comprehensions
Pythagorean quadruples
|
#PHP
|
PHP
|
<?php
function gcd($a, $b)
{
if ($a == 0)
return $b;
if ($b == 0)
return $a;
if($a == $b)
return $a;
if($a > $b)
return gcd($a-$b, $b);
return gcd($a, $b-$a);
}
$pytha = 0;
$prim = 0;
$max_p = 100;
for ($a = 1; $a <= $max_p / 3; $a++) {
$aa = $a**2;
for ($b = $a + 1; $b < $max_p/2; $b++) {
$bb = $b**2;
for ($c = $b + 1; $c < $max_p/2; $c++) {
$cc = $c**2;
if ($aa + $bb < $cc) break;
if ($a + $b + $c > $max_p) break;
if ($aa + $bb == $cc) {
$pytha++;
if (gcd($a, $b) == 1) $prim++;
}
}
}
}
echo 'Up to ' . $max_p . ', there are ' . $pytha . ' triples, of which ' . $prim . ' are primitive.';
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#Objeck
|
Objeck
|
if(problem) {
Runtime->Exit(1);
};
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#OCaml
|
OCaml
|
if problem then
exit integerErrorCode;
(* conventionally, error code 0 is the code for "OK",
while anything else is an actual problem *)
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#Factor
|
Factor
|
USING: formatting grouping io kernel lists lists.lazy math
math.factorials math.functions prettyprint sequences ;
: wilson ( n -- ? ) [ 1 - factorial 1 + ] [ divisor? ] bi ;
: prime? ( n -- ? ) dup 2 < [ drop f ] [ wilson ] if ;
: primes ( -- list ) 1 lfrom [ prime? ] lfilter ;
"n prime?\n--- -----" print
{ 2 3 9 15 29 37 47 57 67 77 87 97 237 409 659 }
[ dup prime? "%-3d %u\n" printf ] each nl
"First 120 primes via Wilson's theorem:" print
120 primes ltake list>array 20 group simple-table. nl
"1000th through 1015th primes:" print
16 primes 999 [ cdr ] times ltake list>array
[ pprint bl ] each nl
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#Fermat
|
Fermat
|
Func Wilson(n) = if ((n-1)!+1)|n = 0 then 1 else 0 fi.;
|
http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#Julia
|
Julia
|
using Printf, Primes
using DataStructures
function counttransitions(upto::Integer)
cnt = counter(Pair{Int,Int})
tot = 0
prv, nxt = 2, 3
while nxt ≤ upto
push!(cnt, prv % 10 => nxt % 10)
prv = nxt
nxt = nextprime(nxt + 1)
tot += 1
end
return sort(Dict(cnt)), tot - 1
end
trans, tot = counttransitions(100_000_000)
println("First 100_000_000 primes, last digit transitions:")
for ((i, j), fr) in trans
@printf("%i → %i: freq. %3.4f%%\n", i, j, 100fr / tot)
end
|
http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#Kotlin
|
Kotlin
|
// version 1.1.2
// compiled with flag -Xcoroutines=enable to suppress 'experimental' warning
import kotlin.coroutines.experimental.*
typealias Transition = Pair<Int, Int>
fun isPrime(n: Int) : Boolean {
if (n < 2) return false
if (n % 2 == 0) return n == 2
if (n % 3 == 0) return n == 3
var d : Int = 5
while (d * d <= n) {
if (n % d == 0) return false
d += 2
if (n % d == 0) return false
d += 4
}
return true
}
fun generatePrimes() =
buildSequence {
yield(2)
var p = 3
while (p <= Int.MAX_VALUE) {
if (isPrime(p)) yield(p)
p += 2
}
}
fun main(args: Array<String>) {
val primes = generatePrimes().take(1_000_000).toList()
val transMap = mutableMapOf<Transition, Int>()
for (i in 0 until primes.size - 1) {
val transition = primes[i] % 10 to primes[i + 1] % 10
if (transMap.containsKey(transition))
transMap[transition] = transMap[transition]!! + 1
else
transMap.put(transition, 1)
}
val sortedTransitions = transMap.keys.sortedBy { it.second }.sortedBy { it.first }
println("First 1,000,000 primes. Transitions prime % 10 -> next-prime % 10.")
for (trans in sortedTransitions) {
print("${trans.first} -> ${trans.second} count: ${"%5d".format(transMap[trans])}")
println(" frequency: ${"%4.2f".format(transMap[trans]!! / 10000.0)}%")
}
}
|
http://rosettacode.org/wiki/Prime_decomposition
|
Prime decomposition
|
The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the prime decomposition of a given number
n
{\displaystyle n}
greater than 1.
If your language does not have an isPrime-like function available,
you may assume that you have a function which determines
whether a number is prime (note its name before your code).
If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes.
Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc).
Related tasks
count in factors
factors of an integer
Sieve of Eratosthenes
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
|
#Applesoft_BASIC
|
Applesoft BASIC
|
9040 PF(0) = 0 : SC = 0
9050 FOR CA = 2 TO INT( SQR(I))
9060 IF I = 1 THEN RETURN
9070 IF INT(I / CA) * CA = I THEN GOSUB 9200 : GOTO 9060
9080 CA = CA + SC : SC = 1
9090 NEXT CA
9100 IF I = 1 THEN RETURN
9110 CA = I
9200 PF(0) = PF(0) + 1
9210 PF(PF(0)) = CA
9220 I = I / CA
9230 RETURN
|
http://rosettacode.org/wiki/Polyspiral
|
Polyspiral
|
A Polyspiral is a spiral made of multiple line segments, whereby each segment is larger (or smaller) than the previous one by a given amount. Each segment also changes direction at a given angle.
Task
Animate a series of polyspirals, by drawing a complete spiral then incrementing the angle, and (after clearing the background) drawing the next, and so on. Every spiral will be a frame of the animation. The animation may stop as it goes full circle or continue indefinitely. The given input values may be varied.
If animation is not practical in your programming environment, you may show a single frame instead.
Pseudo code
set incr to 0.0
// animation loop
WHILE true
incr = (incr + 0.05) MOD 360
x = width / 2
y = height / 2
length = 5
angle = incr
// spiral loop
FOR 1 TO 150
drawline
change direction by angle
length = length + 3
angle = (angle + incr) MOD 360
ENDFOR
|
#C.23
|
C#
|
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;
using System.Windows.Threading;
namespace Polyspiral
{
public partial class Form1 : Form
{
private double inc;
public Form1()
{
Width = Height = 640;
StartPosition = FormStartPosition.CenterScreen;
SetStyle(
ControlStyles.AllPaintingInWmPaint |
ControlStyles.UserPaint |
ControlStyles.DoubleBuffer,
true);
var timer = new DispatcherTimer();
timer.Tick += (s, e) => { inc = (inc + 0.05) % 360; Refresh(); };
timer.Interval = new TimeSpan(0, 0, 0, 0, 40);
timer.Start();
}
private void DrawSpiral(Graphics g, int len, double angleIncrement)
{
double x1 = Width / 2;
double y1 = Height / 2;
double angle = angleIncrement;
for (int i = 0; i < 150; i++)
{
double x2 = x1 + Math.Cos(angle) * len;
double y2 = y1 - Math.Sin(angle) * len;
g.DrawLine(Pens.Blue, (int)x1, (int)y1, (int)x2, (int)y2);
x1 = x2;
y1 = y2;
len += 3;
angle = (angle + angleIncrement) % (Math.PI * 2);
}
}
protected override void OnPaint(PaintEventArgs args)
{
var g = args.Graphics;
g.SmoothingMode = SmoothingMode.AntiAlias;
g.Clear(Color.White);
DrawSpiral(g, 5, ToRadians(inc));
}
private double ToRadians(double angle)
{
return Math.PI * angle / 180.0;
}
}
}
|
http://rosettacode.org/wiki/Power_set
|
Power set
|
A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S.
Task
By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S.
For example, the power set of {1,2,3,4} is
{{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}.
For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set.
The power set of the empty set is the set which contains itself (20 = 1):
P
{\displaystyle {\mathcal {P}}}
(
∅
{\displaystyle \varnothing }
) = {
∅
{\displaystyle \varnothing }
}
And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2):
P
{\displaystyle {\mathcal {P}}}
({
∅
{\displaystyle \varnothing }
}) = {
∅
{\displaystyle \varnothing }
, {
∅
{\displaystyle \varnothing }
} }
Extra credit: Demonstrate that your language supports these last two powersets.
|
#ABAP
|
ABAP
|
report z_powerset.
interface set.
methods:
add_element
importing
element_to_be_added type any
returning
value(new_set) type ref to set,
remove_element
importing
element_to_be_removed type any
returning
value(new_set) type ref to set,
contains_element
importing
element_to_be_found type any
returning
value(contains) type abap_bool,
get_size
returning
value(size) type int4,
is_equal
importing
set_to_be_compared_with type ref to set
returning
value(equal) type abap_bool,
get_elements
exporting
elements type any table,
stringify
returning
value(stringified_set) type string.
endinterface.
class string_set definition.
public section.
interfaces:
set.
methods:
constructor
importing
elements type stringtab optional,
build_powerset
returning
value(powerset) type ref to string_set.
private section.
data elements type stringtab.
endclass.
class string_set implementation.
method constructor.
loop at elements into data(element).
me->set~add_element( element ).
endloop.
endmethod.
method set~add_element.
if not line_exists( me->elements[ table_line = element_to_be_added ] ).
append element_to_be_added to me->elements.
endif.
new_set = me.
endmethod.
method set~remove_element.
if line_exists( me->elements[ table_line = element_to_be_removed ] ).
delete me->elements where table_line = element_to_be_removed.
endif.
new_set = me.
endmethod.
method set~contains_element.
contains = cond abap_bool(
when line_exists( me->elements[ table_line = element_to_be_found ] )
then abap_true
else abap_false ).
endmethod.
method set~get_size.
size = lines( me->elements ).
endmethod.
method set~is_equal.
if set_to_be_compared_with->get_size( ) ne me->set~get_size( ).
equal = abap_false.
return.
endif.
loop at me->elements into data(element).
if not set_to_be_compared_with->contains_element( element ).
equal = abap_false.
return.
endif.
endloop.
equal = abap_true.
endmethod.
method set~get_elements.
elements = me->elements.
endmethod.
method set~stringify.
stringified_set = cond string(
when me->elements is initial
then `∅`
when me->elements eq value stringtab( ( `∅` ) )
then `{ ∅ }`
else reduce string(
init result = `{ `
for element in me->elements
next result = cond string(
when element eq ``
then |{ result }∅, |
when strlen( element ) eq 1 and element ne `∅`
then |{ result }{ element }, |
else |{ result }\{{ element }\}, | ) ) ).
stringified_set = replace(
val = stringified_set
regex = `, $`
with = ` }`).
endmethod.
method build_powerset.
data(powerset_elements) = value stringtab( ( `` ) ).
loop at me->elements into data(element).
do lines( powerset_elements ) times.
if powerset_elements[ sy-index ] ne `∅`.
append |{ powerset_elements[ sy-index ] }{ element }| to powerset_elements.
else.
append element to powerset_elements.
endif.
enddo.
endloop.
powerset = new string_set( powerset_elements ).
endmethod.
endclass.
start-of-selection.
data(set1) = new string_set( ).
data(set2) = new string_set( ).
data(set3) = new string_set( ).
write: |𝑷( { set1->set~stringify( ) } ) -> { set1->build_powerset( )->set~stringify( ) }|, /.
set2->set~add_element( `∅` ).
write: |𝑷( { set2->set~stringify( ) } ) -> { set2->build_powerset( )->set~stringify( ) }|, /.
set3->set~add_element( `1` )->add_element( `2` )->add_element( `3` )->add_element( `3` )->add_element( `4`
)->add_element( `4` )->add_element( `4` ).
write: |𝑷( { set3->set~stringify( ) } ) -> { set3->build_powerset( )->set~stringify( ) }|, /.
|
http://rosettacode.org/wiki/Primality_by_trial_division
|
Primality by trial division
|
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
count in factors
prime decomposition
AKS test for primes
factors of an integer
Sieve of Eratosthenes
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#ACL2
|
ACL2
|
(defun is-prime-r (x i)
(declare (xargs :measure (nfix (- x i))))
(if (zp (- (- x i) 1))
t
(and (/= (mod x i) 0)
(is-prime-r x (1+ i)))))
(defun is-prime (x)
(or (= x 2)
(is-prime-r x 2)))
|
http://rosettacode.org/wiki/Price_fraction
|
Price fraction
|
A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 and 1.00, rescale according to the following table:
>= 0.00 < 0.06 := 0.10
>= 0.06 < 0.11 := 0.18
>= 0.11 < 0.16 := 0.26
>= 0.16 < 0.21 := 0.32
>= 0.21 < 0.26 := 0.38
>= 0.26 < 0.31 := 0.44
>= 0.31 < 0.36 := 0.50
>= 0.36 < 0.41 := 0.54
>= 0.41 < 0.46 := 0.58
>= 0.46 < 0.51 := 0.62
>= 0.51 < 0.56 := 0.66
>= 0.56 < 0.61 := 0.70
>= 0.61 < 0.66 := 0.74
>= 0.66 < 0.71 := 0.78
>= 0.71 < 0.76 := 0.82
>= 0.76 < 0.81 := 0.86
>= 0.81 < 0.86 := 0.90
>= 0.86 < 0.91 := 0.94
>= 0.91 < 0.96 := 0.98
>= 0.96 < 1.01 := 1.00
|
#AutoHotkey
|
AutoHotkey
|
; Submitted by MasterFocus --- http://tiny.cc/iTunis
Loop
{
InputBox, OutputVar, Price Fraction Example, Insert the value to be rounded.`n* [ 0 < value < 1 ]`n* Press ESC or Cancel to exit, , 200, 150
If ErrorLevel
Break
MsgBox % "Input: " OutputVar "`nResult: " PriceFraction( OutputVar )
}
;-----------------------------------------
PriceFraction( p_Input )
{
If p_Input is not float ; returns 0 if input is not a float
Return 0
If ( ( p_Input <= 0 ) OR ( p_Input >= 1 ) ) ; returns 0 is input is out of range
Return 0
; declaring the table (arbitrary delimiters in use are '§' and '|')
l_List := "0.06|0.10§0.11|0.18§0.16|0.26§0.21|0.32§0.26|0.38§0.31|0.44§0.36|0.50§0.41|0.54§0.46|0.58§0.51|0.62§0.56|0.66§0.61|0.70§0.66|0.74§0.71|0.78§0.76|0.82§0.81|0.86§0.86|0.90§0.91|0.94§0.96|0.98§1.01|1.00"
Loop, Parse, l_List, § ; retrieves each field (delimited by '§')
{
StringSplit, l_Array, A_LoopField, | ; splits current field (using delimiter '|')
If ( p_Input <= l_Array1 )
Return l_Array2 ; returns the second value if input <= first value
}
Return 0 ; returns 0, indicating failure (shouldn't be reached though)
}
|
http://rosettacode.org/wiki/Proper_divisors
|
Proper divisors
|
The proper divisors of a positive integer N are those numbers, other than N itself, that divide N without remainder.
For N > 1 they will always include 1, but for N == 1 there are no proper divisors.
Examples
The proper divisors of 6 are 1, 2, and 3.
The proper divisors of 100 are 1, 2, 4, 5, 10, 20, 25, and 50.
Task
Create a routine to generate all the proper divisors of a number.
use it to show the proper divisors of the numbers 1 to 10 inclusive.
Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has.
Show all output here.
Related tasks
Amicable pairs
Abundant, deficient and perfect number classifications
Aliquot sequence classifications
Factors of an integer
Prime decomposition
|
#Delphi
|
Delphi
|
program ProperDivisors;
{$APPTYPE CONSOLE}
{$R *.res}
uses
System.SysUtils,
System.Generics.Collections;
type
TProperDivisors = TArray<Integer>;
function GetProperDivisors(const value: Integer): TProperDivisors;
var
i, count: Integer;
begin
count := 0;
for i := 1 to value div 2 do
begin
if value mod i = 0 then
begin
inc(count);
SetLength(result, count);
Result[count - 1] := i;
end;
end;
end;
procedure Println(values: TProperDivisors);
var
i: Integer;
begin
Write('[');
if Length(values) > 0 then
for i := 0 to High(values) do
Write(Format('%2d', [values[i]]));
Writeln(']');
end;
var
number, max_count, count, max_number: Integer;
begin
for number := 1 to 10 do
begin
write(number, ': ');
Println(GetProperDivisors(number));
end;
max_count := 0;
for number := 1 to 20000 do
begin
count := length(GetProperDivisors(number));
if count > max_count then
begin
max_count := count;
max_number := number;
end;
end;
Write(max_number, ': ', max_count);
readln;
end.
|
http://rosettacode.org/wiki/Probabilistic_choice
|
Probabilistic choice
|
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is involved, this is subject to rounding errors).
aleph 1/5.0
beth 1/6.0
gimel 1/7.0
daleth 1/8.0
he 1/9.0
waw 1/10.0
zayin 1/11.0
heth 1759/27720 # adjusted so that probabilities add to 1
Related task
Random number generator (device)
|
#Forth
|
Forth
|
include random.fs
\ common factors of desired probabilities (1/5 .. 1/11)
2 2 * 2 * 3 * 3 * 5 * 7 * 11 * constant denom \ 27720
\ represent each probability as the numerator with 27720 as the denominator
: ,numerators ( max min -- )
do denom i / , loop ;
\ final item is 27720 - sum(probs)
: ,remainder ( denom addr len -- )
cells bounds do i @ - 1 cells +loop , ;
create probs 12 5 ,numerators denom probs 7 ,remainder
create bins 8 cells allot
: choose ( -- 0..7 )
denom random
8 0 do
probs i cells + @ -
dup 0< if drop i unloop exit then
loop
abort" can't get here" ;
: trials ( n -- )
0 do 1 bins choose cells + +! loop ;
: str-table
create ( c-str ... n -- ) 0 do , loop
does> ( n -- str len ) swap cells + @ count ;
here ," heth" here ," zayin" here ," waw" here ," he"
here ," daleth" here ," gimel" here ," beth" here ," aleph"
8 str-table names
: .header
cr ." Name" #tab emit ." Prob" #tab emit ." Actual" #tab emit ." Error" ;
: .result ( n -- )
cr dup names type #tab emit
dup cells probs + @ s>f denom s>f f/ fdup f. #tab emit
dup cells bins + @ s>f 1e6 f/ fdup f. #tab emit
f- fabs fs. ;
: .results .header 8 0 do i .result loop ;
|
http://rosettacode.org/wiki/Primes_-_allocate_descendants_to_their_ancestors
|
Primes - allocate descendants to their ancestors
|
The concept, is to add the decomposition into prime factors of a number to get its 'ancestors'.
The objective is to demonstrate that the choice of the algorithm can be crucial in term of performance.
This solution could be compared to the solution that would use the decomposition into primes for all the numbers between 1 and 333.
The problem is to list, for a delimited set of ancestors (from 1 to 99) :
- the total of their own ancestors (LEVEL),
- their own ancestors (ANCESTORS),
- the total of the direct descendants (DESCENDANTS),
- all the direct descendants.
You only have to consider the prime factors < 100.
A grand total of the descendants has to be printed at the end of the list.
The task should be accomplished in a reasonable time-frame.
Example :
46 = 2*23 --> 2+23 = 25, is the parent of 46.
25 = 5*5 --> 5+5 = 10, is the parent of 25.
10 = 2*5 --> 2+5 = 7, is the parent of 10.
7 is a prime factor and, as such, has no parent.
46 has 3 ancestors (7, 10 and 25).
46 has 557 descendants.
The list layout and the output for Parent [46] :
[46] Level: 3
Ancestors: 7, 10, 25
Descendants: 557
129, 205, 246, 493, 518, 529, 740, 806, 888, 999, 1364, 1508, 1748, 2552, 2871, 3128, 3255, 3472, 3519, 3875, 3906, 4263, 4650, 4960, 5075, 5415, 5580, 5776, 5952, 6090, 6279, 6496, 6498, 6696, 6783, 7250, 7308, 7475, 7533, 8075, 8151, 8619, 8700, 8855, 8970, 9280, 9568, 9690, 10115, 10336, 10440, 10626, 10764, 11136, 11495, 11628, 11745, 12103, 12138, 12155, 12528, 12650, 13794, 14094, 14399, 14450, 14586, 15180, 15379, 15778, 16192, 17290, 17303, 17340, 18216, 18496, 20482, 20493, 20570, 20748, 20808, 21658, 21970, 22540, 23409, 24684, 24700, 26026, 26364, 27048, 29260, 29282, 29640, 30429, 30940, 31616, 32200, 33345, 35112, 35568, 36225, 36652, 37128, 37180, 38640, 39501, 40014, 41216, 41769, 41800, 43125, 43470, 44044, 44200, 44616, 46000, 46368, 47025, 49725, 50160, 50193, 51750, 52136, 52164, 52360, 53040, 53504, 55200, 56430, 56576, 58653, 58880, 58905, 59670, 60192, 62100, 62832, 62920, 63648, 66240, 66248, 67716, 69825, 70125, 70656, 70686, 70785, 71604, 74480, 74520, 74529, 74536, 74800, 75504, 79488, 83125, 83790, 83835, 83853, 84150, 84942, 87465, 88725, 89376, 89424, 89760, 93296, 94640, 95744, 99750, 99825, 100548, 100602, 100980, 104125, 104958, 105105, 105625, 106400, 106470, 106480, 107712, 112112, 113568, 118750, 119700, 119790, 121176, 124509, 124950, 125125, 126126, 126750, 127680, 127764, 127776, 133280, 135200, 136192, 136323, 142500, 143640, 143748, 148225, 148750, 149940, 150150, 152000, 152100, 153216, 156065, 159936, 160160, 161595, 162240, 171000, 172368, 173056, 177870, 178500, 178750, 179928, 180180, 182400, 182520, 184877, 187278, 189728, 190400, 192192, 192375, 193914, 194560, 194688, 202419, 205200, 205335, 211750, 212500, 213444, 214200, 214500, 216216, 218880, 219024, 222950, 228480, 228800, 230850, 233472, 240975, 243243, 243712, 246240, 246402, 254100, 255000, 257040, 257400, 262656, 264110, 267540, 271040, 272000, 274176, 274560, 277020, 285376, 286875, 289170, 289575, 292864, 295488, 302500, 304920, 306000, 308448, 308880, 316932, 318500, 321048, 325248, 326400, 329472, 332424, 343035, 344250, 347004, 347490, 348160, 361179, 363000, 365904, 367200, 370656, 373977, 377300, 382200, 387200, 391680, 407680, 408375, 411642, 413100, 416988, 417792, 429975, 435600, 440640, 452760, 455000, 458640, 464640, 470016, 470596, 482944, 489216, 490050, 495616, 495720, 509355, 511875, 515970, 522720, 528768, 539000, 543312, 546000, 550368, 557568, 557685, 582400, 588060, 594864, 606375, 609375, 611226, 614250, 619164, 627264, 646800, 650000, 655200, 669222, 672280, 689920, 698880, 705672, 721875, 727650, 731250, 737100, 745472, 756315, 770000, 776160, 780000, 786240, 793881, 806736, 827904, 832000, 838656, 859375, 866250, 873180, 877500, 884520, 900375, 907578, 924000, 931392, 936000, 943488, 960400, 985600, 995085, 998400, 1031250, 1039500, 1047816, 1053000, 1061424, 1064960, 1071875, 1080450, 1100000, 1108800, 1123200, 1152480, 1178793, 1182720, 1184625, 1194102, 1198080, 1229312, 1237500, 1247400, 1261568, 1263600, 1277952, 1286250, 1296540, 1320000, 1330560, 1347840, 1372000, 1382976, 1403325, 1408000, 1419264, 1421550, 1437696, 1485000, 1496880, 1516320, 1531250, 1543500, 1555848, 1584000, 1596672, 1617408, 1646400, 1670625, 1683990, 1689600, 1705860, 1750329, 1756160, 1782000, 1796256, 1802240, 1819584, 1837500, 1852200, 1900800, 1960000, 1975680, 2004750, 2020788, 2027520, 2047032, 2083725, 2107392, 2138400, 2162688, 2187500, 2205000, 2222640, 2280960, 2302911, 2352000, 2370816, 2405700, 2433024, 2480625, 2500470, 2508800, 2566080, 2625000, 2646000, 2667168, 2737152, 2800000, 2822400, 2886840, 2953125, 2976750, 3000564, 3010560, 3079296, 3125000, 3150000, 3175200, 3211264, 3247695, 3360000, 3386880, 3464208, 3515625, 3543750, 3572100, 3584000, 3612672, 3750000, 3780000, 3810240, 3897234, 4000000, 4032000, 4064256, 4218750, 4252500, 4286520, 4300800, 4500000, 4536000, 4572288, 4587520, 4800000, 4822335, 4838400, 5062500, 5103000, 5120000, 5143824, 5160960, 5400000, 5443200, 5505024, 5740875, 5760000, 5786802, 5806080, 6075000, 6123600, 6144000, 6193152, 6480000, 6531840, 6553600, 6834375, 6889050, 6912000, 6967296, 7290000, 7348320, 7372800, 7776000, 7838208, 7864320, 8201250, 8266860, 8294400, 8388608, 8748000, 8817984, 8847360, 9331200, 9437184, 9841500, 9920232, 9953280, 10497600, 10616832, 11160261, 11197440, 11809800, 11943936, 12597120, 13286025, 13436928, 14171760, 15116544, 15943230, 17006112, 19131876
Some figures :
The biggest descendant number : 3^33 = 5.559.060.566.555.523 (parent 99)
Total Descendants 546.986
|
#Wren
|
Wren
|
import "/math" for Int
import "/sort" for Sort
import "/fmt" for Fmt
var maxSum = 99
var descendants = List.filled(maxSum + 1, null)
var ancestors = List.filled(maxSum + 1, null)
for (i in 0..maxSum) {
descendants[i] = []
ancestors[i] = []
}
var primes = Int.primeSieve(maxSum)
for (p in primes) {
descendants[p].add(p)
for (s in 1...descendants.count - p) {
descendants[s + p].addAll(descendants[s].map { |d| p * d })
}
}
for (p in primes + [4]) descendants[p].removeAt(-1)
var total = 0
for (s in 1..maxSum) {
Sort.quick(descendants[s])
total = total + descendants[s].count
for (d in descendants[s]) {
if (d > maxSum) break
ancestors[d] = ancestors[s] + [s]
}
if (s < 21 || s == 46 || s == 74 || s == maxSum) {
Fmt.write("$2d: $d Ancestors[s]: $-18n", s, ancestors[s].count, ancestors[s])
var count = descendants[s].count
var desc10 = (count <= 10) ? descendants[s] : descendants[s].take(10).toList + ["..."]
Fmt.print("$5d Descendants[s]: $n", count, desc10)
}
}
System.print("\nTotal descendants %(total)")
|
http://rosettacode.org/wiki/Priority_queue
|
Priority queue
|
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order.
Task
Create a priority queue. The queue must support at least two operations:
Insertion. An element is added to the queue with a priority (a numeric value).
Top item removal. Deletes the element or one of the elements with the current top priority and return it.
Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc.
To test your implementation, insert a number of elements into the queue, each with some random priority.
Then dequeue them sequentially; now the elements should be sorted by priority.
You can use the following task/priority items as input data:
Priority Task
══════════ ════════════════
3 Clear drains
4 Feed cat
5 Make tea
1 Solve RC tasks
2 Tax return
The implementation should try to be efficient. A typical implementation has O(log n) insertion and extraction time, where n is the number of items in the queue.
You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc. If so, discuss the reasons behind it.
|
#Elixir
|
Elixir
|
defmodule Priority do
def create, do: :gb_trees.empty
def insert( element, priority, queue ), do: :gb_trees.enter( priority, element, queue )
def peek( queue ) do
{_priority, element, _new_queue} = :gb_trees.take_smallest( queue )
element
end
def task do
items = [{3, "Clear drains"}, {4, "Feed cat"}, {5, "Make tea"}, {1, "Solve RC tasks"}, {2, "Tax return"}]
queue = Enum.reduce(items, create, fn({priority, element}, acc) -> insert( element, priority, acc ) end)
IO.puts "peek priority: #{peek( queue )}"
Enum.reduce(1..length(items), queue, fn(_n, q) -> write_top( q ) end)
end
def top( queue ) do
{_priority, element, new_queue} = :gb_trees.take_smallest( queue )
{element, new_queue}
end
defp write_top( q ) do
{element, new_queue} = top( q )
IO.puts "top priority: #{element}"
new_queue
end
end
Priority.task
|
http://rosettacode.org/wiki/Problem_of_Apollonius
|
Problem of Apollonius
|
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the example in the code are shown in the diagram (below and to the right).
The red circle is "internally tangent" to all three black circles, and the green circle is "externally tangent" to all three black circles.
|
#Mathematica.2FWolfram_Language
|
Mathematica/Wolfram Language
|
Apolonius[a1_,b1_,c1_,a2_,b2_,c2_,a3_,b3_,c3_,S1_,S2_ ,S3_ ]:=
Module[{x1=a1,y1=b1,r1=c1,x2=a2,y2=b2,r2=c2,x3=a3,y3=b3,r3=c3,s1=S1,s2=S2,s3=S3},
v11 = 2*x2 - 2*x1; v12 = 2*y2 - 2*y1;
v13 = x1^2 - x2^2 + y1^2 - y2^2 - r1^2 + r2^2;
v14 = 2*s2*r2 - 2*s1*r1;
v21 = 2*x3-2*x2 ; v22 = 2*y3 - 2*y2;
v23 = x2^2 - x3^2 + y2^2 - y3^2 - r2^2 + r3^2;
v24 = 2*s3*r3 - 2*s2*r2;
w12 = v12/v11; w13 = v13/v11; w14 = v14/v11;
w22 = v22/v21 - w12;
w23 = v23/v21 - w13;
w24 = v24/v21 - w14;
p = -w23/w22; q=w24/w22;
m = -w12*p - w13; n=w14 - w12*q;
a = n^2 + q^2-1;
b = 2*m*n - 2*n*x1 + 2*p*q - 2*q*y1 + 2*s1*r1;
c = x1^2+m^2 - 2*m*x1 + p^2+y1^2 - 2*p*y1 - r1^2;
d= b^2 - 4*a*c;
rs = (-b -Sqrt[d])/(2*a);
xs = m + n*rs; ys = p + q*rs;
Map[N,{xs, ys, rs} ]]
|
http://rosettacode.org/wiki/Problem_of_Apollonius
|
Problem of Apollonius
|
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the example in the code are shown in the diagram (below and to the right).
The red circle is "internally tangent" to all three black circles, and the green circle is "externally tangent" to all three black circles.
|
#MUMPS
|
MUMPS
|
APOLLONIUS(CIR1,CIR2,CIR3,S1,S2,S3)
;Circles are passed in as strings with three parts with a "^" separator in the order x^y^r
;The three circles are CIR1, CIR2, and CIR3
;The S1, S2, and S3 parameters determine if the solution will be internally or externally
;tangent to the circle. (+1 external, -1 internal)
;CIRR is the circle returned in the same format as the input circles
;
;Xn, Yn, and Rn are the values for a circle n - following the precedents from the
;other examples because doing $Pieces would make this confusing to read
NEW X1,X2,X3,Y1,Y2,Y3,R1,R2,R3,RS,V11,V12,V13,V14,V21,V22,V23,V24,W12,W13,W14,W22,W23,W24,P,M,N,Q,A,B,C,D
NEW CIRR
SET X1=$PIECE(CIR1,"^",1),X2=$PIECE(CIR2,"^",1),X3=$PIECE(CIR3,"^",1)
SET Y1=$PIECE(CIR1,"^",2),Y2=$PIECE(CIR2,"^",2),Y3=$PIECE(CIR3,"^",2)
SET R1=$PIECE(CIR1,"^",3),R2=$PIECE(CIR2,"^",3),R3=$PIECE(CIR3,"^",3)
SET V11=(2*X2)-(2*X1)
SET V12=(2*Y2)-(2*Y1)
SET V13=(X1*X1)-(X2*X2)+(Y1*Y1)-(Y2*Y2)-(R1*R1)+(R2*R2)
SET V14=(2*S2*R2)-(2*S1*R1)
SET V21=(2*X3)-(2*X2)
SET V22=(2*Y3)-(2*Y2)
SET V23=(X2*X2)-(X3*X3)+(Y2*Y2)-(Y3*Y3)-(R2*R2)+(R3*R3)
SET V24=(2*S3*R3)-(2*S2*R2)
SET W12=V12/V11
SET W13=V13/V11
SET W14=V14/V11
SET W22=(V22/V21)-W12 ;Parentheses for insurance - MUMPS evaluates left to right
SET W23=(V23/V21)-W13
SET W24=(V24/V21)-W14
SET P=-W23/W22
SET Q=W24/W22
SET M=-(W12*P)-W13
SET N=W14-(W12*Q)
SET A=(N*N)+(Q*Q)-1
SET B=(2*M*N)-(2*N*X1)+(2*P*Q)-(2*Q*Y1)+(2*S1*R1)
SET C=(X1*X1)+(M*M)+(2*M*X1)+(P*P)+(Y1*Y1)-(2*P*Y1)-(R1*R1)
SET D=(B*B)-(4*A*C)
SET RS=(-B-(D**.5))/(2*A)
SET $PIECE(CIRR,"^",1)=M+(N*RS)
SET $PIECE(CIRR,"^",2)=P+(Q*RS)
SET $PIECE(CIRR,"^",3)=RS
KILL X1,X2,X3,Y1,Y2,Y3,R1,R2,R3,RS,V11,V12,V13,V14,V21,V22,V23,V24,W12,W13,W14,W22,W23,W24,P,M,N,Q,A,B,C,D
QUIT CIRR
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#PowerShell
|
PowerShell
|
# write this in file <program.ps1>
$MyInvocation.MyCommand.Name
# launch with <.\program>
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#Prolog
|
Prolog
|
% SWI-Prolog version 8.0.0 for i686-linux.
% This will find itself, and return the knowledge base it is in.
file_name(F) :- true
, M = user % M is the module .
, P = file_name(_) % P is the predicate .
, source_file(M:P, F) % F is the file .
, \+ predicate_property(M:P, imported_from(_))
.
|
http://rosettacode.org/wiki/Pythagorean_triples
|
Pythagorean triples
|
A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displaystyle a,b,c}
are co-prime, that is, if their pairwise greatest common divisors
g
c
d
(
a
,
b
)
=
g
c
d
(
a
,
c
)
=
g
c
d
(
b
,
c
)
=
1
{\displaystyle {\rm {gcd}}(a,b)={\rm {gcd}}(a,c)={\rm {gcd}}(b,c)=1}
.
Because of their relationship through the Pythagorean theorem, a, b, and c are co-prime if a and b are co-prime (
g
c
d
(
a
,
b
)
=
1
{\displaystyle {\rm {gcd}}(a,b)=1}
).
Each triple forms the length of the sides of a right triangle, whose perimeter is
P
=
a
+
b
+
c
{\displaystyle P=a+b+c}
.
Task
The task is to determine how many Pythagorean triples there are with a perimeter no larger than 100 and the number of these that are primitive.
Extra credit
Deal with large values. Can your program handle a maximum perimeter of 1,000,000? What about 10,000,000? 100,000,000?
Note: the extra credit is not for you to demonstrate how fast your language is compared to others; you need a proper algorithm to solve them in a timely manner.
Related tasks
Euler's sum of powers conjecture
List comprehensions
Pythagorean quadruples
|
#Picat
|
Picat
|
main :-
garbage_collect(300_000_000),
Data = [100, 1_000, 10_000, 100_000, 1_000_000, 10_000_000, 100_000_000],
member(Max, Data),
count_triples(Max, Total, Prim),
printf("upto %d, there are %d Pythagorean triples (%d primitive.)%n", Max, Total, Prim),
fail,
nl.
count_triples(Max, Total, Prims) :-
Ps = findall(S, (triple(Max, A, B, C), S is A + B + C)),
Prims = Ps.len,
Total = sum([Max div P : P in Ps]).
% - between_by/4
between_by(A, B, N, K) :-
C = (B - A) div N,
between(0, C, J),
K = N*J + A.
% - Pythagorean triple generator
triple(P, A, B, C) :-
Max = floor(sqrt(P/2)) - 1,
between(0, Max, M),
Start = (M /\ 1) + 1,
Pm = M - 1,
between_by(Start, Pm, 2, N),
gcd(M, N) == 1,
X = M*M - N*N,
Y = 2*M*N,
C = M*M + N*N,
order2(X, Y, A, B),
(A + B + C) =< P.
order2(A, B, A, B) :- A < B, !.
order2(A, B, B, A).
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#Oforth
|
Oforth
|
import: os
some_condition ifTrue: [ 0 OS.exit ]
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#Ol
|
Ol
|
(shutdown 0) ; it can be any exit code instead of provided 0
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#Forth
|
Forth
|
: fac-mod ( n m -- r )
>r 1 swap
begin dup 0> while
dup rot * r@ mod swap 1-
repeat drop rdrop ;
: ?prime ( n -- f )
dup 1- tuck swap fac-mod = ;
: .primes ( n -- )
cr 2 ?do i ?prime if i . then loop ;
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#FreeBASIC
|
FreeBASIC
|
function wilson_prime( n as uinteger ) as boolean
dim as uinteger fct=1, i
for i = 2 to n-1
'because (a mod n)*b = (ab mod n)
'it is not necessary to calculate the entire factorial
fct = (fct * i) mod n
next i
if fct = n-1 then return true else return false
end function
for i as uinteger = 2 to 100
if wilson_prime(i) then print i,
next i
|
http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#Lua
|
Lua
|
-- Return boolean indicating whether or not n is prime
function isPrime (n)
if n <= 1 then return false end
if n <= 3 then return true end
if n % 2 == 0 or n % 3 == 0 then return false end
local i = 5
while i * i <= n do
if n % i == 0 or n % (i + 2) == 0 then return false end
i = i + 6
end
return true
end
-- Return table of frequencies for final digits of consecutive primes
function primeCon (limit)
local count, x, last, ending = 2, 3, 3
local freqList = {
[1] = {},
[2] = {[3] = 1},
[3] = {},
[5] = {},
[7] = {},
[9] = {}
}
repeat
x = x + 2
if isPrime(x) then
ending = x % 10
if freqList[last][ending] then
freqList[last][ending] = freqList[last][ending] + 1
else
freqList[last][ending] = 1
end
last = ending
count = count + 1
end
until count == limit
return freqList
end
-- Main procedure
local limit = 10^6
local t = primeCon(limit)
for a = 1, 9 do
for b = 1, 9 do
if t[a] and t[a][b] then
io.write(a .. " -> " .. b .. "\tcount: " .. t[a][b])
print("\tfrequency: " .. t[a][b] / limit * 100 .. " %")
end
end
end
|
http://rosettacode.org/wiki/Prime_decomposition
|
Prime decomposition
|
The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the prime decomposition of a given number
n
{\displaystyle n}
greater than 1.
If your language does not have an isPrime-like function available,
you may assume that you have a function which determines
whether a number is prime (note its name before your code).
If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes.
Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc).
Related tasks
count in factors
factors of an integer
Sieve of Eratosthenes
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
|
#Arturo
|
Arturo
|
decompose: function [num][
facts: to [:string] factors.prime num
print [
pad.right (to :string num) ++ " = " ++ join.with:" x " facts 30
"{"++ (join.with:", " unique facts) ++ "}"
]
]
loop 2..40 => decompose
|
http://rosettacode.org/wiki/Polyspiral
|
Polyspiral
|
A Polyspiral is a spiral made of multiple line segments, whereby each segment is larger (or smaller) than the previous one by a given amount. Each segment also changes direction at a given angle.
Task
Animate a series of polyspirals, by drawing a complete spiral then incrementing the angle, and (after clearing the background) drawing the next, and so on. Every spiral will be a frame of the animation. The animation may stop as it goes full circle or continue indefinitely. The given input values may be varied.
If animation is not practical in your programming environment, you may show a single frame instead.
Pseudo code
set incr to 0.0
// animation loop
WHILE true
incr = (incr + 0.05) MOD 360
x = width / 2
y = height / 2
length = 5
angle = incr
// spiral loop
FOR 1 TO 150
drawline
change direction by angle
length = length + 3
angle = (angle + incr) MOD 360
ENDFOR
|
#C.2B.2B
|
C++
|
#include <windows.h>
#include <sstream>
#include <ctime>
const float PI = 3.1415926536f, TWO_PI = 2.f * PI;
class vector2
{
public:
vector2( float a = 0, float b = 0 ) { set( a, b ); }
void set( float a, float b ) { x = a; y = b; }
void rotate( float r ) {
float _x = x, _y = y,
s = sinf( r ), c = cosf( r ),
a = _x * c - _y * s, b = _x * s + _y * c;
x = a; y = b;
}
vector2 add( const vector2& v ) {
x += v.x; y += v.y;
return *this;
}
float x, y;
};
class myBitmap
{
public:
myBitmap() : pen( NULL ), brush( NULL ), clr( 0 ), wid( 1 ) {}
~myBitmap(){
DeleteObject( pen );
DeleteObject( brush );
DeleteDC( hdc );
DeleteObject( bmp );
}
bool create( int w, int h ){
BITMAPINFO bi;
ZeroMemory( &bi, sizeof( bi ) );
bi.bmiHeader.biSize = sizeof( bi.bmiHeader );
bi.bmiHeader.biBitCount = sizeof( DWORD ) * 8;
bi.bmiHeader.biCompression = BI_RGB;
bi.bmiHeader.biPlanes = 1;
bi.bmiHeader.biWidth = w;
bi.bmiHeader.biHeight = -h;
HDC dc = GetDC( GetConsoleWindow() );
bmp = CreateDIBSection( dc, &bi, DIB_RGB_COLORS, &pBits, NULL, 0 );
if( !bmp ) return false;
hdc = CreateCompatibleDC( dc );
SelectObject( hdc, bmp );
ReleaseDC( GetConsoleWindow(), dc );
width = w; height = h;
return true;
}
void clear( BYTE clr = 0 ){
memset( pBits, clr, width * height * sizeof( DWORD ) );
}
void setBrushColor( DWORD bClr ){
if( brush ) DeleteObject( brush );
brush = CreateSolidBrush( bClr );
SelectObject( hdc, brush );
}
void setPenColor( DWORD c ){
clr = c; createPen();
}
void setPenWidth( int w ){
wid = w; createPen();
}
void saveBitmap( std::string path ){
BITMAPFILEHEADER fileheader;
BITMAPINFO infoheader;
BITMAP bitmap;
DWORD wb;
GetObject( bmp, sizeof( bitmap ), &bitmap );
DWORD* dwpBits = new DWORD[bitmap.bmWidth * bitmap.bmHeight];
ZeroMemory( dwpBits, bitmap.bmWidth * bitmap.bmHeight * sizeof( DWORD ) );
ZeroMemory( &infoheader, sizeof( BITMAPINFO ) );
ZeroMemory( &fileheader, sizeof( BITMAPFILEHEADER ) );
infoheader.bmiHeader.biBitCount = sizeof( DWORD ) * 8;
infoheader.bmiHeader.biCompression = BI_RGB;
infoheader.bmiHeader.biPlanes = 1;
infoheader.bmiHeader.biSize = sizeof( infoheader.bmiHeader );
infoheader.bmiHeader.biHeight = bitmap.bmHeight;
infoheader.bmiHeader.biWidth = bitmap.bmWidth;
infoheader.bmiHeader.biSizeImage = bitmap.bmWidth * bitmap.bmHeight * sizeof( DWORD );
fileheader.bfType = 0x4D42;
fileheader.bfOffBits = sizeof( infoheader.bmiHeader ) + sizeof( BITMAPFILEHEADER );
fileheader.bfSize = fileheader.bfOffBits + infoheader.bmiHeader.biSizeImage;
GetDIBits( hdc, bmp, 0, height, ( LPVOID )dwpBits, &infoheader, DIB_RGB_COLORS );
HANDLE file = CreateFile( path.c_str(), GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL );
WriteFile( file, &fileheader, sizeof( BITMAPFILEHEADER ), &wb, NULL );
WriteFile( file, &infoheader.bmiHeader, sizeof( infoheader.bmiHeader ), &wb, NULL );
WriteFile( file, dwpBits, bitmap.bmWidth * bitmap.bmHeight * 4, &wb, NULL );
CloseHandle( file );
delete [] dwpBits;
}
HDC getDC() const { return hdc; }
int getWidth() const { return width; }
int getHeight() const { return height; }
private:
void createPen(){
if( pen ) DeleteObject( pen );
pen = CreatePen( PS_SOLID, wid, clr );
SelectObject( hdc, pen );
}
HBITMAP bmp; HDC hdc;
HPEN pen; HBRUSH brush;
void *pBits; int width, height, wid;
DWORD clr;
};
int main( int argc, char* argv[] ) {
srand( unsigned( time( 0 ) ) );
myBitmap bmp;
bmp.create( 600, 600 ); bmp.clear();
HDC dc = bmp.getDC();
float fs = ( TWO_PI ) / 100.f;
int index = 0;
std::string a = "f://users//images//test", b;
float ang, len;
vector2 p1, p2;
for( float step = 0.1f; step < 5.1f; step += .05f ) {
ang = 0; len = 2;
p1.set( 300, 300 );
bmp.setPenColor( RGB( rand() % 50 + 200, rand() % 300 + 220, rand() % 50 + 200 ) );
for( float xx = 0; xx < TWO_PI; xx += fs ) {
MoveToEx( dc, (int)p1.x, (int)p1.y, NULL );
p2.set( 0, len ); p2.rotate( ang ); p2.add( p1 );
LineTo( dc, (int)p2.x, (int)p2.y );
p1 = p2; ang += step; len += step;
}
std::ostringstream ss; ss << index++;
b = a + ss.str() + ".bmp";
bmp.saveBitmap( b );
bmp.clear();
}
return 0;
}
|
http://rosettacode.org/wiki/Polynomial_regression
|
Polynomial regression
|
Find an approximating polynomial of known degree for a given data.
Example:
For input data:
x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321};
The approximating polynomial is:
3 x2 + 2 x + 1
Here, the polynomial's coefficients are (3, 2, 1).
This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
|
#11l
|
11l
|
F average(arr)
R sum(arr) / Float(arr.len)
F poly_regression(x, y)
V xm = average(x)
V ym = average(y)
V x2m = average(x.map(i -> i * i))
V x3m = average(x.map(i -> i ^ 3))
V x4m = average(x.map(i -> i ^ 4))
V xym = average(zip(x, y).map((i, j) -> i * j))
V x2ym = average(zip(x, y).map((i, j) -> i * i * j))
V sxx = x2m - xm * xm
V sxy = xym - xm * ym
V sxx2 = x3m - xm * x2m
V sx2x2 = x4m - x2m * x2m
V sx2y = x2ym - x2m * ym
V b = (sxy * sx2x2 - sx2y * sxx2) / (sxx * sx2x2 - sxx2 * sxx2)
V c = (sx2y * sxx - sxy * sxx2) / (sxx * sx2x2 - sxx2 * sxx2)
V a = ym - b * xm - c * x2m
F abc(xx)
R (@a + @b * xx) + (@c * xx * xx)
print("y = #. + #.x + #.x^2\n".format(a, b, c))
print(‘ Input Approximation’)
print(‘ x y y1’)
L(i) 0 .< x.len
print(‘#2 #3 #3.1’.format(x[i], y[i], abc(i)))
V x = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
V y = [1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321]
poly_regression(x, y)
|
http://rosettacode.org/wiki/Power_set
|
Power set
|
A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S.
Task
By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S.
For example, the power set of {1,2,3,4} is
{{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}.
For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set.
The power set of the empty set is the set which contains itself (20 = 1):
P
{\displaystyle {\mathcal {P}}}
(
∅
{\displaystyle \varnothing }
) = {
∅
{\displaystyle \varnothing }
}
And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2):
P
{\displaystyle {\mathcal {P}}}
({
∅
{\displaystyle \varnothing }
}) = {
∅
{\displaystyle \varnothing }
, {
∅
{\displaystyle \varnothing }
} }
Extra credit: Demonstrate that your language supports these last two powersets.
|
#Ada
|
Ada
|
with Ada.Text_IO, Ada.Command_Line;
use Ada.Text_IO, Ada.Command_Line;
procedure powerset is
begin
for set in 0..2**Argument_Count-1 loop
Put ("{");
declare
k : natural := set;
first : boolean := true;
begin
for i in 1..Argument_Count loop
if k mod 2 = 1 then
Put ((if first then "" else ",") & Argument (i));
first := false;
end if;
k := k / 2; -- we go to the next bit of "set"
end loop;
end;
Put_Line("}");
end loop;
end powerset;
|
http://rosettacode.org/wiki/Primality_by_trial_division
|
Primality by trial division
|
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
count in factors
prime decomposition
AKS test for primes
factors of an integer
Sieve of Eratosthenes
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#Action.21
|
Action!
|
BYTE FUNC IsPrime(CARD a)
CARD i
IF a<=1 THEN
RETURN (0)
FI
FOR i=2 TO a/2
DO
IF a MOD i=0 THEN
RETURN (0)
FI
OD
RETURN (1)
PROC Test(CARD a)
IF IsPrime(a) THEN
PrintF("%I is prime%E",a)
ELSE
PrintF("%I is not prime%E",a)
FI
RETURN
PROC Main()
Test(13)
Test(997)
Test(1)
Test(6)
Test(120)
Test(0)
RETURN
|
http://rosettacode.org/wiki/Price_fraction
|
Price fraction
|
A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 and 1.00, rescale according to the following table:
>= 0.00 < 0.06 := 0.10
>= 0.06 < 0.11 := 0.18
>= 0.11 < 0.16 := 0.26
>= 0.16 < 0.21 := 0.32
>= 0.21 < 0.26 := 0.38
>= 0.26 < 0.31 := 0.44
>= 0.31 < 0.36 := 0.50
>= 0.36 < 0.41 := 0.54
>= 0.41 < 0.46 := 0.58
>= 0.46 < 0.51 := 0.62
>= 0.51 < 0.56 := 0.66
>= 0.56 < 0.61 := 0.70
>= 0.61 < 0.66 := 0.74
>= 0.66 < 0.71 := 0.78
>= 0.71 < 0.76 := 0.82
>= 0.76 < 0.81 := 0.86
>= 0.81 < 0.86 := 0.90
>= 0.86 < 0.91 := 0.94
>= 0.91 < 0.96 := 0.98
>= 0.96 < 1.01 := 1.00
|
#AWK
|
AWK
|
BEGIN {
O = ".06 .11 .16 .21 .26 .31 .36 .41 .46 .51 .56 .61 .66 .71 .76 .81 .86 .91 .96 1.01"
N = ".10 .18 .26 .32 .38 .44 .50 .54 .58 .62 .66 .70 .74 .78 .82 .86 .90 .94 .98 1.00"
fields = split(O,Oarr," ") # original values
split(N,Narr," ") # replacement values
for (i=-.01; i<=1.02; i+=.01) { # test
printf("%5.2f = %4.2f\n",i,lookup(i))
}
}
function lookup(n, i) {
if (n < 0 || n > 1.01) {
return(0) # when input is out of range
}
for (i=1; i<=fields; i++) {
# +10 is used because .11 returned .18 instead of .26
# under AWK95, GAWK, and MAWK; Thompson Automation's TAWK worked correctly
if (n+10 < Oarr[i]+10) {
return(Narr[i])
}
}
}
|
http://rosettacode.org/wiki/Proper_divisors
|
Proper divisors
|
The proper divisors of a positive integer N are those numbers, other than N itself, that divide N without remainder.
For N > 1 they will always include 1, but for N == 1 there are no proper divisors.
Examples
The proper divisors of 6 are 1, 2, and 3.
The proper divisors of 100 are 1, 2, 4, 5, 10, 20, 25, and 50.
Task
Create a routine to generate all the proper divisors of a number.
use it to show the proper divisors of the numbers 1 to 10 inclusive.
Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has.
Show all output here.
Related tasks
Amicable pairs
Abundant, deficient and perfect number classifications
Aliquot sequence classifications
Factors of an integer
Prime decomposition
|
#Dyalect
|
Dyalect
|
func properDivs(n) {
if n == 1 {
yield break
}
for x in 1..<n {
if n % x == 0 {
yield x
}
}
}
for i in 1..10 {
print("\(i): \(properDivs(i).ToArray())")
}
var (num, max) = (0,0)
for i in 1..20000 {
let count = properDivs(i).Length()
if count > max {
set (num, max) = (i, count)
}
}
print("\(num): \(max)")
|
http://rosettacode.org/wiki/Probabilistic_choice
|
Probabilistic choice
|
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is involved, this is subject to rounding errors).
aleph 1/5.0
beth 1/6.0
gimel 1/7.0
daleth 1/8.0
he 1/9.0
waw 1/10.0
zayin 1/11.0
heth 1759/27720 # adjusted so that probabilities add to 1
Related task
Random number generator (device)
|
#Fortran
|
Fortran
|
PROGRAM PROBS
IMPLICIT NONE
INTEGER, PARAMETER :: trials = 1000000
INTEGER :: i, j, probcount(8) = 0
REAL :: expected(8), mapping(8), rnum
CHARACTER(6) :: items(8) = (/ "aleph ", "beth ", "gimel ", "daleth", "he ", "waw ", "zayin ", "heth " /)
expected(1:7) = (/ (1.0/i, i=5,11) /)
expected(8) = 1.0 - SUM(expected(1:7))
mapping(1) = 1.0 / 5.0
DO i = 2, 7
mapping(i) = mapping(i-1) + 1.0/(i+4.0)
END DO
mapping(8) = 1.0
DO i = 1, trials
CALL RANDOM_NUMBER(rnum)
DO j = 1, 8
IF (rnum < mapping(j)) THEN
probcount(j) = probcount(j) + 1
EXIT
END IF
END DO
END DO
WRITE(*, "(A,I10)") "Trials: ", trials
WRITE(*, "(A,8A10)") "Items: ", items
WRITE(*, "(A,8F10.6)") "Target Probability: ", expected
WRITE(*, "(A,8F10.6)") "Attained Probability:", REAL(probcount) / REAL(trials)
ENDPROGRAM PROBS
|
http://rosettacode.org/wiki/Primes_-_allocate_descendants_to_their_ancestors
|
Primes - allocate descendants to their ancestors
|
The concept, is to add the decomposition into prime factors of a number to get its 'ancestors'.
The objective is to demonstrate that the choice of the algorithm can be crucial in term of performance.
This solution could be compared to the solution that would use the decomposition into primes for all the numbers between 1 and 333.
The problem is to list, for a delimited set of ancestors (from 1 to 99) :
- the total of their own ancestors (LEVEL),
- their own ancestors (ANCESTORS),
- the total of the direct descendants (DESCENDANTS),
- all the direct descendants.
You only have to consider the prime factors < 100.
A grand total of the descendants has to be printed at the end of the list.
The task should be accomplished in a reasonable time-frame.
Example :
46 = 2*23 --> 2+23 = 25, is the parent of 46.
25 = 5*5 --> 5+5 = 10, is the parent of 25.
10 = 2*5 --> 2+5 = 7, is the parent of 10.
7 is a prime factor and, as such, has no parent.
46 has 3 ancestors (7, 10 and 25).
46 has 557 descendants.
The list layout and the output for Parent [46] :
[46] Level: 3
Ancestors: 7, 10, 25
Descendants: 557
129, 205, 246, 493, 518, 529, 740, 806, 888, 999, 1364, 1508, 1748, 2552, 2871, 3128, 3255, 3472, 3519, 3875, 3906, 4263, 4650, 4960, 5075, 5415, 5580, 5776, 5952, 6090, 6279, 6496, 6498, 6696, 6783, 7250, 7308, 7475, 7533, 8075, 8151, 8619, 8700, 8855, 8970, 9280, 9568, 9690, 10115, 10336, 10440, 10626, 10764, 11136, 11495, 11628, 11745, 12103, 12138, 12155, 12528, 12650, 13794, 14094, 14399, 14450, 14586, 15180, 15379, 15778, 16192, 17290, 17303, 17340, 18216, 18496, 20482, 20493, 20570, 20748, 20808, 21658, 21970, 22540, 23409, 24684, 24700, 26026, 26364, 27048, 29260, 29282, 29640, 30429, 30940, 31616, 32200, 33345, 35112, 35568, 36225, 36652, 37128, 37180, 38640, 39501, 40014, 41216, 41769, 41800, 43125, 43470, 44044, 44200, 44616, 46000, 46368, 47025, 49725, 50160, 50193, 51750, 52136, 52164, 52360, 53040, 53504, 55200, 56430, 56576, 58653, 58880, 58905, 59670, 60192, 62100, 62832, 62920, 63648, 66240, 66248, 67716, 69825, 70125, 70656, 70686, 70785, 71604, 74480, 74520, 74529, 74536, 74800, 75504, 79488, 83125, 83790, 83835, 83853, 84150, 84942, 87465, 88725, 89376, 89424, 89760, 93296, 94640, 95744, 99750, 99825, 100548, 100602, 100980, 104125, 104958, 105105, 105625, 106400, 106470, 106480, 107712, 112112, 113568, 118750, 119700, 119790, 121176, 124509, 124950, 125125, 126126, 126750, 127680, 127764, 127776, 133280, 135200, 136192, 136323, 142500, 143640, 143748, 148225, 148750, 149940, 150150, 152000, 152100, 153216, 156065, 159936, 160160, 161595, 162240, 171000, 172368, 173056, 177870, 178500, 178750, 179928, 180180, 182400, 182520, 184877, 187278, 189728, 190400, 192192, 192375, 193914, 194560, 194688, 202419, 205200, 205335, 211750, 212500, 213444, 214200, 214500, 216216, 218880, 219024, 222950, 228480, 228800, 230850, 233472, 240975, 243243, 243712, 246240, 246402, 254100, 255000, 257040, 257400, 262656, 264110, 267540, 271040, 272000, 274176, 274560, 277020, 285376, 286875, 289170, 289575, 292864, 295488, 302500, 304920, 306000, 308448, 308880, 316932, 318500, 321048, 325248, 326400, 329472, 332424, 343035, 344250, 347004, 347490, 348160, 361179, 363000, 365904, 367200, 370656, 373977, 377300, 382200, 387200, 391680, 407680, 408375, 411642, 413100, 416988, 417792, 429975, 435600, 440640, 452760, 455000, 458640, 464640, 470016, 470596, 482944, 489216, 490050, 495616, 495720, 509355, 511875, 515970, 522720, 528768, 539000, 543312, 546000, 550368, 557568, 557685, 582400, 588060, 594864, 606375, 609375, 611226, 614250, 619164, 627264, 646800, 650000, 655200, 669222, 672280, 689920, 698880, 705672, 721875, 727650, 731250, 737100, 745472, 756315, 770000, 776160, 780000, 786240, 793881, 806736, 827904, 832000, 838656, 859375, 866250, 873180, 877500, 884520, 900375, 907578, 924000, 931392, 936000, 943488, 960400, 985600, 995085, 998400, 1031250, 1039500, 1047816, 1053000, 1061424, 1064960, 1071875, 1080450, 1100000, 1108800, 1123200, 1152480, 1178793, 1182720, 1184625, 1194102, 1198080, 1229312, 1237500, 1247400, 1261568, 1263600, 1277952, 1286250, 1296540, 1320000, 1330560, 1347840, 1372000, 1382976, 1403325, 1408000, 1419264, 1421550, 1437696, 1485000, 1496880, 1516320, 1531250, 1543500, 1555848, 1584000, 1596672, 1617408, 1646400, 1670625, 1683990, 1689600, 1705860, 1750329, 1756160, 1782000, 1796256, 1802240, 1819584, 1837500, 1852200, 1900800, 1960000, 1975680, 2004750, 2020788, 2027520, 2047032, 2083725, 2107392, 2138400, 2162688, 2187500, 2205000, 2222640, 2280960, 2302911, 2352000, 2370816, 2405700, 2433024, 2480625, 2500470, 2508800, 2566080, 2625000, 2646000, 2667168, 2737152, 2800000, 2822400, 2886840, 2953125, 2976750, 3000564, 3010560, 3079296, 3125000, 3150000, 3175200, 3211264, 3247695, 3360000, 3386880, 3464208, 3515625, 3543750, 3572100, 3584000, 3612672, 3750000, 3780000, 3810240, 3897234, 4000000, 4032000, 4064256, 4218750, 4252500, 4286520, 4300800, 4500000, 4536000, 4572288, 4587520, 4800000, 4822335, 4838400, 5062500, 5103000, 5120000, 5143824, 5160960, 5400000, 5443200, 5505024, 5740875, 5760000, 5786802, 5806080, 6075000, 6123600, 6144000, 6193152, 6480000, 6531840, 6553600, 6834375, 6889050, 6912000, 6967296, 7290000, 7348320, 7372800, 7776000, 7838208, 7864320, 8201250, 8266860, 8294400, 8388608, 8748000, 8817984, 8847360, 9331200, 9437184, 9841500, 9920232, 9953280, 10497600, 10616832, 11160261, 11197440, 11809800, 11943936, 12597120, 13286025, 13436928, 14171760, 15116544, 15943230, 17006112, 19131876
Some figures :
The biggest descendant number : 3^33 = 5.559.060.566.555.523 (parent 99)
Total Descendants 546.986
|
#zkl
|
zkl
|
const maxsum=99;
primes:=Utils.Generator(Import("sieve.zkl").postponed_sieve)
.pump(List,'wrap(p){ (p<=maxsum) and p or Void.Stop });
descendants,ancestors:=List()*(maxsum + 1), List()*(maxsum + 1);
foreach p in (primes){
descendants[p].insert(0,p);
foreach s in ([1..descendants.len() - p - 1]){
descendants[s + p].merge(descendants[s].apply('*(p)));
}
}
// descendants[prime] is a list that starts with prime, remove prime. 4: ???
foreach p in (primes + 4) { descendants[p].pop(0) }
ta,td:=0,0;
foreach s in ([1..maxsum]){
foreach d in (descendants[s].filter('<=(maxsum))){
ancestors[d]=ancestors[s].copy() + s;
}
println("%2d Ancestors: ".fmt(s),ancestors[s].len() and ancestors[s] or "None");
println(" Descendants: ", if(z:=descendants[s])
String(z.len()," : ",z) else "None");
ta+=ancestors[s].len(); td+=descendants[s].len();
}
println("Total ancestors: %,d".fmt(ta));
println("Total descendants: %,d".fmt(td));
|
http://rosettacode.org/wiki/Priority_queue
|
Priority queue
|
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order.
Task
Create a priority queue. The queue must support at least two operations:
Insertion. An element is added to the queue with a priority (a numeric value).
Top item removal. Deletes the element or one of the elements with the current top priority and return it.
Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc.
To test your implementation, insert a number of elements into the queue, each with some random priority.
Then dequeue them sequentially; now the elements should be sorted by priority.
You can use the following task/priority items as input data:
Priority Task
══════════ ════════════════
3 Clear drains
4 Feed cat
5 Make tea
1 Solve RC tasks
2 Tax return
The implementation should try to be efficient. A typical implementation has O(log n) insertion and extraction time, where n is the number of items in the queue.
You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc. If so, discuss the reasons behind it.
|
#Erlang
|
Erlang
|
-module( priority_queue ).
-export( [create/0, insert/3, peek/1, task/0, top/1] ).
create() -> gb_trees:empty().
insert( Element, Priority, Queue ) -> gb_trees:enter( Priority, Element, Queue ).
peek( Queue ) ->
{_Priority, Element, _New_queue} = gb_trees:take_smallest( Queue ),
Element.
task() ->
Items = [{3, "Clear drains"}, {4, "Feed cat"}, {5, "Make tea"}, {1, "Solve RC tasks"}, {2, "Tax return"}],
Queue = lists:foldl( fun({Priority, Element}, Acc) -> insert( Element, Priority, Acc ) end, create(), Items ),
io:fwrite( "peek priority: ~p~n", [peek( Queue )] ),
lists:foldl( fun(_N, Q) -> write_top( Q ) end, Queue, lists:seq(1, erlang:length(Items)) ).
top( Queue ) ->
{_Priority, Element, New_queue} = gb_trees:take_smallest( Queue ),
{Element, New_queue}.
write_top( Q ) ->
{Element, New_queue} = top( Q ),
io:fwrite( "top priority: ~p~n", [Element] ),
New_queue.
|
http://rosettacode.org/wiki/Problem_of_Apollonius
|
Problem of Apollonius
|
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the example in the code are shown in the diagram (below and to the right).
The red circle is "internally tangent" to all three black circles, and the green circle is "externally tangent" to all three black circles.
|
#Nim
|
Nim
|
import math
type Circle = tuple[x, y, r: float]
proc solveApollonius(c1, c2, c3: Circle; s1, s2, s3: float): Circle =
let
v11 = 2*c2.x - 2*c1.x
v12 = 2*c2.y - 2*c1.y
v13 = c1.x*c1.x - c2.x*c2.x + c1.y*c1.y - c2.y*c2.y - c1.r*c1.r + c2.r*c2.r
v14 = 2*s2*c2.r - 2*s1*c1.r
v21 = 2*c3.x - 2*c2.x
v22 = 2*c3.y - 2*c2.y
v23 = c2.x*c2.x - c3.x*c3.x + c2.y*c2.y - c3.y*c3.y - c2.r*c2.r + c3.r*c3.r
v24 = 2*s3*c3.r - 2*s2*c2.r
w12 = v12/v11
w13 = v13/v11
w14 = v14/v11
w22 = v22/v21-w12
w23 = v23/v21-w13
w24 = v24/v21-w14
p = -w23/w22
q = w24/w22
m = -w12*p-w13
n = w14 - w12*q
a = n*n + q*q - 1
b = 2*m*n - 2*n*c1.x + 2*p*q - 2*q*c1.y + 2*s1*c1.r
c = c1.x*c1.x + m*m - 2*m*c1.x + p*p + c1.y*c1.y - 2*p*c1.y - c1.r*c1.r
d = b*b-4*a*c
rs = (-b-sqrt(d))/(2*a)
xs = m+n*rs
ys = p+q*rs
return (xs, ys, rs)
let
c1: Circle = (0.0, 0.0, 1.0)
c2: Circle = (4.0, 0.0, 1.0)
c3: Circle = (2.0, 4.0, 2.0)
echo solveApollonius(c1, c2, c3, 1.0, 1.0, 1.0)
echo solveApollonius(c1, c2, c3, -1.0, -1.0, -1.0)
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#PureBasic
|
PureBasic
|
If OpenConsole()
PrintN(ProgramFilename())
Print(#CRLF$ + #CRLF$ + "Press ENTER to exit"): Input()
CloseConsole()
EndIf
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#Python
|
Python
|
#!/usr/bin/env python
import sys
def main():
program = sys.argv[0]
print("Program: %s" % program)
if __name__ == "__main__":
main()
|
http://rosettacode.org/wiki/Pythagorean_triples
|
Pythagorean triples
|
A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displaystyle a,b,c}
are co-prime, that is, if their pairwise greatest common divisors
g
c
d
(
a
,
b
)
=
g
c
d
(
a
,
c
)
=
g
c
d
(
b
,
c
)
=
1
{\displaystyle {\rm {gcd}}(a,b)={\rm {gcd}}(a,c)={\rm {gcd}}(b,c)=1}
.
Because of their relationship through the Pythagorean theorem, a, b, and c are co-prime if a and b are co-prime (
g
c
d
(
a
,
b
)
=
1
{\displaystyle {\rm {gcd}}(a,b)=1}
).
Each triple forms the length of the sides of a right triangle, whose perimeter is
P
=
a
+
b
+
c
{\displaystyle P=a+b+c}
.
Task
The task is to determine how many Pythagorean triples there are with a perimeter no larger than 100 and the number of these that are primitive.
Extra credit
Deal with large values. Can your program handle a maximum perimeter of 1,000,000? What about 10,000,000? 100,000,000?
Note: the extra credit is not for you to demonstrate how fast your language is compared to others; you need a proper algorithm to solve them in a timely manner.
Related tasks
Euler's sum of powers conjecture
List comprehensions
Pythagorean quadruples
|
#PicoLisp
|
PicoLisp
|
(for (Max 10 (>= 100000000 Max) (* Max 10))
(let (Total 0 Prim 0 In (3 4 5))
(recur (In)
(let P (apply + In)
(when (>= Max P)
(inc 'Prim)
(inc 'Total (/ Max P))
(for Row
(quote
(( 1 -2 2) ( 2 -1 2) ( 2 -2 3))
(( 1 2 2) ( 2 1 2) ( 2 2 3))
((-1 2 2) (-2 1 2) (-2 2 3)) )
(recurse
(mapcar '((U) (sum * U In)) Row) ) ) ) ) )
(prinl "Up to " Max ": " Total " triples, " Prim " primitives.") ) )
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#Oz
|
Oz
|
if Problem then {Application.exit 0} end
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#PARI.2FGP
|
PARI/GP
|
if(stuff, quit)
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#F.C5.8Drmul.C3.A6
|
Fōrmulæ
|
# find primes using Wilson's theorem:
# p is prime if ( ( p - 1 )! + 1 ) mod p = 0
isWilsonPrime := function( p )
local fModP, i;
fModP := 1;
for i in [ 2 .. p - 1 ] do fModP := fModP * i; fModP := fModP mod p; od;
return fModP = p - 1;
end; # isWilsonPrime
prime := [];
for i in [ -4 .. 100 ] do if isWilsonPrime( i ) then Add( prime, i ); fi; od;
Display( prime );
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#GAP
|
GAP
|
# find primes using Wilson's theorem:
# p is prime if ( ( p - 1 )! + 1 ) mod p = 0
isWilsonPrime := function( p )
local fModP, i;
fModP := 1;
for i in [ 2 .. p - 1 ] do fModP := fModP * i; fModP := fModP mod p; od;
return fModP = p - 1;
end; # isWilsonPrime
prime := [];
for i in [ -4 .. 100 ] do if isWilsonPrime( i ) then Add( prime, i ); fi; od;
Display( prime );
|
http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#Mathematica.2FWolfram_Language
|
Mathematica/Wolfram Language
|
StringForm["`` count: `` frequency: ``", Rule@@ #[[1]], StringPadLeft[ToString@ #[[2]], 8], PercentForm[N@ #[[2]]/(10^8 -1)]]& /@
Sort[Tally[Partition[Mod[Prime[Range[10^8]], 10], 2, 1]]] // Column
|
http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#Nim
|
Nim
|
# Prime conspiracy.
from algorithm import sorted
from math import sqrt
from sequtils import toSeq
from strformat import fmt
import tables
const N = 1_020_000_000.int # Size of sieve of Eratosthenes.
proc newSieve(): seq[bool] =
## Create a sieve with only odd values.
## Index "i" in sieve represents value "n = 2 * i + 3".
result.setLen(N)
for item in result.mitems: item = true
# Apply sieve.
var i = 0
const Limit = sqrt(2 * N.toFloat + 3).int
while true:
let n = 2 * i + 3
if n > Limit:
break
if result[i]:
# Found prime, so eliminate multiples.
for k in countup((n * n - 3) div 2, N - 1, n):
result[k] = false
inc i
var isPrime = newSieve()
proc countTransitions(isPrime: seq[bool]; nprimes: int) =
## Build the transition count table and print it.
var counts = [(2, 3)].toCountTable() # Count of transitions.
var d1 = 3 # Last digit of first prime in transition.
var count = 2 # Count of primes (starting with 2 and 3).
for i in 1..isPrime.high:
if isPrime[i]:
inc count
let d2 = (2 * i + 3) mod 10 # Last digit of second prime in transition.
counts.inc((d1, d2))
if count == nprimes: break
d1 = d2
# Check if sieve was big enough.
if count < nprimes:
echo fmt"Found only {count} primes; expected {nprimes} primes. Increase value of N."
quit(QuitFailure)
# Print result.
echo fmt"{nprimes} first primes. Transitions prime % 10 → next-prime % 10."
for key in sorted(toSeq(counts.keys)):
let count = counts[key]
let freq = count.toFloat * 100 / nprimes.toFloat
echo fmt"{key[0]} -> {key[1]}: count: {count:7d} frequency: {freq:4.2f}%"
echo ""
isPrime.countTransitions(10_000)
isPrime.countTransitions(1_000_000)
isPrime.countTransitions(100_000_000)
|
http://rosettacode.org/wiki/Prime_decomposition
|
Prime decomposition
|
The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the prime decomposition of a given number
n
{\displaystyle n}
greater than 1.
If your language does not have an isPrime-like function available,
you may assume that you have a function which determines
whether a number is prime (note its name before your code).
If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes.
Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc).
Related tasks
count in factors
factors of an integer
Sieve of Eratosthenes
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
|
#AutoHotkey
|
AutoHotkey
|
MsgBox % factor(8388607) ; 47 * 178481
factor(n)
{
if (n = 1)
return
f = 2
while (f <= n)
{
if (Mod(n, f) = 0)
{
next := factor(n / f)
return, % f "`n" next
}
f++
}
}
|
http://rosettacode.org/wiki/Polyspiral
|
Polyspiral
|
A Polyspiral is a spiral made of multiple line segments, whereby each segment is larger (or smaller) than the previous one by a given amount. Each segment also changes direction at a given angle.
Task
Animate a series of polyspirals, by drawing a complete spiral then incrementing the angle, and (after clearing the background) drawing the next, and so on. Every spiral will be a frame of the animation. The animation may stop as it goes full circle or continue indefinitely. The given input values may be varied.
If animation is not practical in your programming environment, you may show a single frame instead.
Pseudo code
set incr to 0.0
// animation loop
WHILE true
incr = (incr + 0.05) MOD 360
x = width / 2
y = height / 2
length = 5
angle = incr
// spiral loop
FOR 1 TO 150
drawline
change direction by angle
length = length + 3
angle = (angle + incr) MOD 360
ENDFOR
|
#Ceylon
|
Ceylon
|
import javafx.application {
Application
}
import javafx.stage {
Stage
}
import javafx.animation {
AnimationTimer
}
import ceylon.numeric.float {
remainder,
cos,
sin,
toRadians
}
import javafx.scene.layout {
BorderPane
}
import javafx.scene.canvas {
Canvas
}
import javafx.scene {
Scene
}
import javafx.scene.paint {
Color
}
shared void run() {
Application.launch(`PolySpiralApp`);
}
shared class PolySpiralApp() extends Application() {
value width = 600.0;
value height = 600.0;
variable value incr = 0.0;
shared actual void start(Stage primaryStage) {
value canvas = Canvas(width, height);
value graphics = canvas.graphicsContext2D;
object extends AnimationTimer() {
shared actual void handle(Integer now) {
incr = remainder(incr + 0.05, 360.0);
variable value x = width / 2.0;
variable value y = width / 2.0;
variable value length = 5.0;
variable value angle = incr;
graphics.fillRect(0.0, 0.0, width, height);
graphics.beginPath();
graphics.moveTo(x, y);
for (i in 1..150) {
value radians = toRadians(angle);
x = x + cos(radians) * length;
y = y + sin(radians) * length;
graphics.stroke = Color.hsb(angle, 1.0, 1.0);
graphics.lineTo(x, y);
length += 3;
angle = remainder(angle + incr, 360.0);
}
graphics.stroke();
}
}.start();
value root = BorderPane();
root.center = canvas;
value scene = Scene(root);
primaryStage.title = "poly-spiral";
primaryStage.setScene(scene);
primaryStage.show();
}
}
|
http://rosettacode.org/wiki/Polyspiral
|
Polyspiral
|
A Polyspiral is a spiral made of multiple line segments, whereby each segment is larger (or smaller) than the previous one by a given amount. Each segment also changes direction at a given angle.
Task
Animate a series of polyspirals, by drawing a complete spiral then incrementing the angle, and (after clearing the background) drawing the next, and so on. Every spiral will be a frame of the animation. The animation may stop as it goes full circle or continue indefinitely. The given input values may be varied.
If animation is not practical in your programming environment, you may show a single frame instead.
Pseudo code
set incr to 0.0
// animation loop
WHILE true
incr = (incr + 0.05) MOD 360
x = width / 2
y = height / 2
length = 5
angle = incr
// spiral loop
FOR 1 TO 150
drawline
change direction by angle
length = length + 3
angle = (angle + incr) MOD 360
ENDFOR
|
#FreeBASIC
|
FreeBASIC
|
#include "fbgfx.bi"
#if __FB_LANG__ = "fb"
Using FB '' Scan code constants are stored in the FB namespace in lang FB
#endif
#define pi 4 * Atn(1)
#define Deg2Rad pi/180
Dim As Integer w = 900, h = w
Screenres w, h, 8
Windowtitle "Polyspiral"
Dim As Integer incr = 0, angulo, longitud, x1, y1, x2, y2, N
Do
incr += 1
x1 = w / 2
y1 = h / 2
Pset (Fix(x1), Fix(y1))
longitud = 5
angulo = incr
For N = 1 To 150
x2 = x1 + longitud * Cos(angulo * Deg2Rad)
y2 = y1 + longitud * Sin(angulo * Deg2Rad)
Line - (Fix(x2), Fix(y2)), N+16
x1 = x2
y1 = y2
longitud += 3
angulo += incr
Next N
Sleep 500
Cls
Loop Until Multikey(SC_ESCAPE)
|
http://rosettacode.org/wiki/Polynomial_regression
|
Polynomial regression
|
Find an approximating polynomial of known degree for a given data.
Example:
For input data:
x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321};
The approximating polynomial is:
3 x2 + 2 x + 1
Here, the polynomial's coefficients are (3, 2, 1).
This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
|
#Ada
|
Ada
|
with Ada.Numerics.Real_Arrays; use Ada.Numerics.Real_Arrays;
function Fit (X, Y : Real_Vector; N : Positive) return Real_Vector is
A : Real_Matrix (0..N, X'Range); -- The plane
begin
for I in A'Range (2) loop
for J in A'Range (1) loop
A (J, I) := X (I)**J;
end loop;
end loop;
return Solve (A * Transpose (A), A * Y);
end Fit;
|
http://rosettacode.org/wiki/Power_set
|
Power set
|
A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S.
Task
By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S.
For example, the power set of {1,2,3,4} is
{{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}.
For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set.
The power set of the empty set is the set which contains itself (20 = 1):
P
{\displaystyle {\mathcal {P}}}
(
∅
{\displaystyle \varnothing }
) = {
∅
{\displaystyle \varnothing }
}
And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2):
P
{\displaystyle {\mathcal {P}}}
({
∅
{\displaystyle \varnothing }
}) = {
∅
{\displaystyle \varnothing }
, {
∅
{\displaystyle \varnothing }
} }
Extra credit: Demonstrate that your language supports these last two powersets.
|
#ALGOL_68
|
ALGOL 68
|
MODE MEMBER = INT;
PROC power set = ([]MEMBER s)[][]MEMBER:(
[2**UPB s]FLEX[1:0]MEMBER r;
INT upb r := 0;
r[upb r +:= 1] := []MEMBER(());
FOR i TO UPB s DO
MEMBER e = s[i];
FOR j TO upb r DO
[UPB r[j] + 1]MEMBER x;
x[:UPB x-1] := r[j];
x[UPB x] := e; # append to the end of x #
r[upb r +:= 1] := x # append to end of r #
OD
OD;
r[upb r] := s;
r
);
# Example: #
test:(
[][]MEMBER set = power set((1, 2, 4));
FOR member TO UPB set DO
INT upb = UPB set[member];
FORMAT repr set = $"("f( upb=0 | $$ | $n(upb-1)(d", ")d$ )");"$;
printf(($"set["d"] = "$,member, repr set, set[member],$l$))
OD
)
|
http://rosettacode.org/wiki/Primality_by_trial_division
|
Primality by trial division
|
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
count in factors
prime decomposition
AKS test for primes
factors of an integer
Sieve of Eratosthenes
factors of a Mersenne number
trial factoring of a Mersenne number
partition an integer X into N primes
sequence of primes by Trial Division
|
#ActionScript
|
ActionScript
|
function isPrime(n:int):Boolean
{
if(n < 2) return false;
if(n == 2) return true;
if((n & 1) == 0) return false;
for(var i:int = 3; i <= Math.sqrt(n); i+= 2)
if(n % i == 0) return false;
return true;
}
|
http://rosettacode.org/wiki/Price_fraction
|
Price fraction
|
A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 and 1.00, rescale according to the following table:
>= 0.00 < 0.06 := 0.10
>= 0.06 < 0.11 := 0.18
>= 0.11 < 0.16 := 0.26
>= 0.16 < 0.21 := 0.32
>= 0.21 < 0.26 := 0.38
>= 0.26 < 0.31 := 0.44
>= 0.31 < 0.36 := 0.50
>= 0.36 < 0.41 := 0.54
>= 0.41 < 0.46 := 0.58
>= 0.46 < 0.51 := 0.62
>= 0.51 < 0.56 := 0.66
>= 0.56 < 0.61 := 0.70
>= 0.61 < 0.66 := 0.74
>= 0.66 < 0.71 := 0.78
>= 0.71 < 0.76 := 0.82
>= 0.76 < 0.81 := 0.86
>= 0.81 < 0.86 := 0.90
>= 0.86 < 0.91 := 0.94
>= 0.91 < 0.96 := 0.98
>= 0.96 < 1.01 := 1.00
|
#BASIC
|
BASIC
|
DECLARE FUNCTION PriceFraction! (price AS SINGLE)
RANDOMIZE TIMER
DIM x AS SINGLE
x = RND
PRINT x, PriceFraction(x)
FUNCTION PriceFraction! (price AS SINGLE)
'returns price unchanged if invalid value
SELECT CASE price
CASE IS < 0!
PriceFraction! = price
CASE IS < .06
PriceFraction! = .1
CASE IS < .11
PriceFraction! = .18
CASE IS < .16
PriceFraction! = .26
CASE IS < .21
PriceFraction! = .32
CASE IS < .26
PriceFraction! = .38
CASE IS < .31
PriceFraction! = .44
CASE IS < .36
PriceFraction! = .5
CASE IS < .41
PriceFraction! = .54
CASE IS < .46
PriceFraction! = .58
CASE IS < .51
PriceFraction! = .62
CASE IS < .56
PriceFraction! = .66
CASE IS < .61
PriceFraction! = .7
CASE IS < .66
PriceFraction! = .74
CASE IS < .71
PriceFraction! = .78
CASE IS < .76
PriceFraction! = .82
CASE IS < .81
PriceFraction! = .86
CASE IS < .86
PriceFraction! = .9
CASE IS < .91
PriceFraction! = .94
CASE IS < .96
PriceFraction! = .98
CASE IS < 1.01
PriceFraction! = 1!
CASE ELSE
PriceFraction! = price
END SELECT
END FUNCTION
|
http://rosettacode.org/wiki/Proper_divisors
|
Proper divisors
|
The proper divisors of a positive integer N are those numbers, other than N itself, that divide N without remainder.
For N > 1 they will always include 1, but for N == 1 there are no proper divisors.
Examples
The proper divisors of 6 are 1, 2, and 3.
The proper divisors of 100 are 1, 2, 4, 5, 10, 20, 25, and 50.
Task
Create a routine to generate all the proper divisors of a number.
use it to show the proper divisors of the numbers 1 to 10 inclusive.
Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has.
Show all output here.
Related tasks
Amicable pairs
Abundant, deficient and perfect number classifications
Aliquot sequence classifications
Factors of an integer
Prime decomposition
|
#EchoLisp
|
EchoLisp
|
(lib 'list) ;; list-delete
;; let n = product p_i^a_i , p_i prime
;; number of divisors = product (a_i + 1) - 1
(define (numdivs n)
(1- (apply * (map (lambda(g) (1+ (length g))) (group (prime-factors n))))))
(remember 'numdivs)
;; prime powers
;; input : a list g of grouped prime factors ( 3 3 3 ..)
;; returns (1 3 9 27 ...)
(define (ppows g (mult 1))
(for/fold (ppows '(1)) ((a g))
(set! mult (* mult a))
(cons mult ppows)))
;; proper divisors
;; decomp n into ((2 2 ..) ( 3 3 ..) ) prime factors groups
;; combines (1 2 4 8 ..) (1 3 9 ..) lists
;; remove n from the list
(define (divs n)
(if (<= n 1) null
(list-delete
(for/fold (divs'(1)) ((g (map ppows (group (prime-factors n)))))
(for*/list ((a divs) (b g)) (* a b)))
n )))
;; find number(s) with max # of proper divisors
;; returns list of (n . maxdivs) for n in range 2..N
(define (most-proper N)
(define maxdivs 1)
(define ndivs 0)
(for/fold (most-proper null) ((n (in-range 2 N)))
(set! ndivs (numdivs n))
#:continue (< ndivs maxdivs)
(when (> ndivs maxdivs)
(set!-values (most-proper maxdivs) (values null ndivs)))
(cons (cons n maxdivs) most-proper)))
|
http://rosettacode.org/wiki/Probabilistic_choice
|
Probabilistic choice
|
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is involved, this is subject to rounding errors).
aleph 1/5.0
beth 1/6.0
gimel 1/7.0
daleth 1/8.0
he 1/9.0
waw 1/10.0
zayin 1/11.0
heth 1759/27720 # adjusted so that probabilities add to 1
Related task
Random number generator (device)
|
#FreeBASIC
|
FreeBASIC
|
' FB 1.05.0 Win64
Dim letters (0 To 7) As String = {"aleph", "beth", "gimel", "daleth", "he", "waw", "zayin", "heth"}
Dim actual (0 To 7) As Integer '' all zero by default
Dim probs (0 To 7) As Double = {1/5.0, 1/6.0, 1/7.0, 1/8.0, 1/9.0, 1/10.0, 1/11.0}
Dim cumProbs (0 To 7) As Double
cumProbs(0) = probs(0)
For i As Integer = 1 To 6
cumProbs(i) = cumProbs(i - 1) + probs(i)
Next
cumProbs(7) = 1.0
probs(7) = 1.0 - cumProbs(6)
Randomize
Dim rand As Double
Dim n As Double = 1000000
Dim sum As Double = 0.0
For i As Integer = 1 To n
rand = Rnd '' random number where 0 <= rand < 1
Select case rand
Case Is <= cumProbs(0)
actual(0) += 1
Case Is <= cumProbs(1)
actual(1) += 1
Case Is <= cumProbs(2)
actual(2) += 1
Case Is <= cumProbs(3)
actual(3) += 1
Case Is <= cumProbs(4)
actual(4) += 1
Case Is <= cumProbs(5)
actual(5) += 1
Case Is <= cumProbs(6)
actual(6) += 1
Case Else
actual(7) += 1
End Select
Next
Dim sumActual As Double = 0
Print "Letter", " Actual", "Expected"
Print "------", "--------", "--------"
For i As Integer = 0 To 7
Print letters(i),
Print Using "#.######"; actual(i)/n;
sumActual += actual(i)/n
Print , Using "#.######"; probs(i)
Next
Print , "--------", "--------"
Print , Using "#.######"; sumActual;
Print , Using "#.######"; 1.000000
Print
Print "Press any key to quit"
Sleep
|
http://rosettacode.org/wiki/Priority_queue
|
Priority queue
|
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order.
Task
Create a priority queue. The queue must support at least two operations:
Insertion. An element is added to the queue with a priority (a numeric value).
Top item removal. Deletes the element or one of the elements with the current top priority and return it.
Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc.
To test your implementation, insert a number of elements into the queue, each with some random priority.
Then dequeue them sequentially; now the elements should be sorted by priority.
You can use the following task/priority items as input data:
Priority Task
══════════ ════════════════
3 Clear drains
4 Feed cat
5 Make tea
1 Solve RC tasks
2 Tax return
The implementation should try to be efficient. A typical implementation has O(log n) insertion and extraction time, where n is the number of items in the queue.
You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc. If so, discuss the reasons behind it.
|
#F.23
|
F#
|
[<RequireQualifiedAccess>]
module PriorityQ =
// type 'a treeElement = Element of uint32 * 'a
type 'a treeElement = struct val k:uint32 val v:'a new(k,v) = { k=k;v=v } end
type 'a tree = Node of uint32 * 'a treeElement * 'a tree list
type 'a heap = 'a tree list
[<CompilationRepresentation(CompilationRepresentationFlags.UseNullAsTrueValue)>]
[<NoEquality; NoComparison>]
type 'a outerheap = | HeapEmpty | HeapNotEmpty of 'a treeElement * 'a heap
let empty = HeapEmpty
let isEmpty = function | HeapEmpty -> true | _ -> false
let inline private rank (Node(r,_,_)) = r
let inline private root (Node(_,x,_)) = x
exception Empty_Heap
let peekMin = function | HeapEmpty -> None
| HeapNotEmpty(min, _) -> Some (min.k, min.v)
let rec private findMin heap =
match heap with | [] -> raise Empty_Heap //guarded so should never happen
| [node] -> root node,[]
| topnode::heap' ->
let min,subheap = findMin heap' in let rtn = root topnode
match subheap with
| [] -> if rtn.k > min.k then min,[] else rtn,[]
| minnode::heap'' ->
let rmn = root minnode
if rtn.k <= rmn.k then rtn,heap
else rmn,minnode::topnode::heap''
let private mergeTree (Node(r,kv1,ts1) as tree1) (Node (_,kv2,ts2) as tree2) =
if kv1.k > kv2.k then Node(r+1u,kv2,tree1::ts2)
else Node(r+1u,kv1,tree2::ts1)
let rec private insTree (newnode: 'a tree) heap =
match heap with
| [] -> [newnode]
| topnode::heap' -> if (rank newnode) < (rank topnode) then newnode::heap
else insTree (mergeTree newnode topnode) heap'
let push k v = let kv = treeElement(k,v) in let nn = Node(0u,kv,[])
function | HeapEmpty -> HeapNotEmpty(kv,[nn])
| HeapNotEmpty(min,heap) -> let nmin = if k > min.k then min else kv
HeapNotEmpty(nmin,insTree nn heap)
let rec private merge' heap1 heap2 = //doesn't guaranty minimum tree node as head!!!
match heap1,heap2 with
| _,[] -> heap1
| [],_ -> heap2
| topheap1::heap1',topheap2::heap2' ->
match compare (rank topheap1) (rank topheap2) with
| -1 -> topheap1::merge' heap1' heap2
| 1 -> topheap2::merge' heap1 heap2'
| _ -> insTree (mergeTree topheap1 topheap2) (merge' heap1' heap2')
let merge oheap1 oheap2 = match oheap1,oheap2 with
| _,HeapEmpty -> oheap1
| HeapEmpty,_ -> oheap2
| HeapNotEmpty(min1,heap1),HeapNotEmpty(min2,heap2) ->
let min = if min1.k > min2.k then min2 else min1
HeapNotEmpty(min,merge' heap1 heap2)
let rec private removeMinTree = function
| [] -> raise Empty_Heap // will never happen as already guarded
| [node] -> node,[]
| t::ts -> let t',ts' = removeMinTree ts
if (root t).k <= (root t').k then t,ts else t',t::ts'
let deleteMin =
function | HeapEmpty -> HeapEmpty
| HeapNotEmpty(_,heap) ->
match heap with
| [] -> HeapEmpty // should never occur: non empty heap with no elements
| [Node(_,_,heap')] -> match heap' with
| [] -> HeapEmpty
| _ -> let min,_ = findMin heap'
HeapNotEmpty(min,heap')
| _::_ -> let Node(_,_,ts1),ts2 = removeMinTree heap
let nheap = merge' (List.rev ts1) ts2 in let min,_ = findMin nheap
HeapNotEmpty(min,nheap)
let replaceMin k v pq = push k v (deleteMin pq)
let fromSeq sq = Seq.fold (fun pq (k, v) -> push k v pq) empty sq
let popMin pq = match peekMin pq with
| None -> None
| Some(kv) -> Some(kv, deleteMin pq)
let toSeq pq = Seq.unfold popMin pq
let sort sq = sq |> fromSeq |> toSeq
let adjust f pq = pq |> toSeq |> Seq.map (fun (k, v) -> f k v) |> fromSeq
|
http://rosettacode.org/wiki/Problem_of_Apollonius
|
Problem of Apollonius
|
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the example in the code are shown in the diagram (below and to the right).
The red circle is "internally tangent" to all three black circles, and the green circle is "externally tangent" to all three black circles.
|
#OCaml
|
OCaml
|
type point = { x:float; y:float }
type circle = {
center: point;
radius: float;
}
let new_circle ~x ~y ~r =
{ center = { x=x; y=y };
radius = r }
let print_circle ~c =
Printf.printf "Circle(x=%.2f, y=%.2f, r=%.2f)\n"
c.center.x c.center.y c.radius
let defxyr c =
(c.center.x,
c.center.y,
c.radius)
let solve_apollonius ~c1 ~c2 ~c3
~s1 ~s2 ~s3 =
let ( * ) = ( *. ) in
let ( / ) = ( /. ) in
let ( + ) = ( +. ) in
let ( - ) = ( -. ) in
let x1, y1, r1 = defxyr c1
and x2, y2, r2 = defxyr c2
and x3, y3, r3 = defxyr c3 in
let v11 = 2.0 * x2 - 2.0 * x1
and v12 = 2.0 * y2 - 2.0 * y1
and v13 = x1*x1 - x2*x2 + y1*y1 - y2*y2 - r1*r1 + r2*r2
and v14 = (2.0 * s2 * r2) - (2.0 * s1 * r1)
and v21 = 2.0 * x3 - 2.0 * x2
and v22 = 2.0 * y3 - 2.0 * y2
and v23 = x2*x2 - x3*x3 + y2*y2 - y3*y3 - r2*r2 + r3*r3
and v24 = (2.0 * s3 * r3) - (2.0 * s2 * r2) in
let w12 = v12 / v11
and w13 = v13 / v11
and w14 = v14 / v11 in
let w22 = v22 / v21 - w12
and w23 = v23 / v21 - w13
and w24 = v24 / v21 - w14 in
let p = -. w23 / w22
and q = w24 / w22 in
let m = -. w12 * p - w13
and n = w14 - w12 * q in
let a = n*n + q*q - 1.0
and b = 2.0*m*n - 2.0*n*x1 + 2.0*p*q - 2.0*q*y1 + 2.0*s1*r1
and c = x1*x1 + m*m - 2.0*m*x1 + p*p + y1*y1 - 2.0*p*y1 - r1*r1 in
let d = b * b - 4.0 * a * c in
let rs = (-. b - (sqrt d)) / (2.0 * a) in
let xs = m + n * rs
and ys = p + q * rs in
(new_circle xs ys rs)
let () =
let c1 = new_circle 0.0 0.0 1.0
and c2 = new_circle 4.0 0.0 1.0
and c3 = new_circle 2.0 4.0 2.0 in
let r1 = solve_apollonius c1 c2 c3 1.0 1.0 1.0 in
print_circle r1;
let r2 = solve_apollonius c1 c2 c3 (-1.) (-1.) (-1.) in
print_circle r2;
;;
|
http://rosettacode.org/wiki/Program_name
|
Program name
|
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal ARGV.
See also Command-line arguments
Examples from GitHub.
|
#R
|
R
|
#!/usr/bin/env Rscript
getProgram <- function(args) {
sub("--file=", "", args[grep("--file=", args)])
}
args <- commandArgs(trailingOnly = FALSE)
program <- getProgram(args)
cat("Program: ", program, "\n")
q("no")
|
http://rosettacode.org/wiki/Pythagorean_triples
|
Pythagorean triples
|
A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displaystyle a,b,c}
are co-prime, that is, if their pairwise greatest common divisors
g
c
d
(
a
,
b
)
=
g
c
d
(
a
,
c
)
=
g
c
d
(
b
,
c
)
=
1
{\displaystyle {\rm {gcd}}(a,b)={\rm {gcd}}(a,c)={\rm {gcd}}(b,c)=1}
.
Because of their relationship through the Pythagorean theorem, a, b, and c are co-prime if a and b are co-prime (
g
c
d
(
a
,
b
)
=
1
{\displaystyle {\rm {gcd}}(a,b)=1}
).
Each triple forms the length of the sides of a right triangle, whose perimeter is
P
=
a
+
b
+
c
{\displaystyle P=a+b+c}
.
Task
The task is to determine how many Pythagorean triples there are with a perimeter no larger than 100 and the number of these that are primitive.
Extra credit
Deal with large values. Can your program handle a maximum perimeter of 1,000,000? What about 10,000,000? 100,000,000?
Note: the extra credit is not for you to demonstrate how fast your language is compared to others; you need a proper algorithm to solve them in a timely manner.
Related tasks
Euler's sum of powers conjecture
List comprehensions
Pythagorean quadruples
|
#PL.2FI
|
PL/I
|
*process source attributes xref or(!);
/*********************************************************************
* REXX pgm counts number of Pythagorean triples
* that exist given a max perimeter of N,
* and also counts how many of them are primatives.
* 05.05.2013 Walter Pachl translated from REXX version 2
*********************************************************************/
pyt: Proc Options(main);
Dcl sysprint Print;
Dcl (addr,mod,right) Builtin;
Dcl memn Bin Fixed(31) Init(0);
Dcl mabca(300) Char(12);
Dcl 1 mabc,
2 ma Dec fixed(7),
2 mb Dec fixed(7),
2 mc Dec fixed(7);
Dcl mabce Char(12) Based(addr(mabc));
Dcl 1 abc,
2 a Dec fixed(7),
2 b Dec fixed(7),
2 c Dec fixed(7);
Dcl abce Char(12) Based(addr(abc));
Dcl (prims,trips,m,n,aa,aabb,cc,aeven,ab) Dec Fixed(7);
mabca='';
trips=0;
prims=0;
n=100;
la:
Do a=3 To n/3;
aa=a*a; /* limit side to 1/3 of perimeter.*/
aeven=mod(a,2)=0;
lb:Do b=a+1 By 1+aeven; /* triangle can't be isosceles. */
ab=a+b; /* compute partial perimeter. */
If ab>=n Then
Iterate la; /* a+b>perimeter? Try different A*/
aabb=aa+b*b; /* compute sum of a² + b² (cheat)*/
Do c=b+1 By 1;
cc=c*c; /* 3rd side: also compute c² */
If aeven Then
If mod(c,2)=0 Then
Iterate;
If ab+c>n Then
Iterate la; /* a+b+c > perimeter? Try diff A.*/
If cc>aabb Then
Iterate lb; /* c² > a²+b² ? Try different B.*/
If cc^=aabb Then
Iterate; /* c² ¬= a²+b² ? Try different C.*/
If mema(abce) Then
Iterate;
trips=trips+1; /* eureka. */
prims=prims+1; /* count this primitive triple. */
Put Edit(a,b,c,' ',right(a**2+b**2,5),right(c**2,5),a+b+c)
(Skip,f(4),2(f(5)),a,2(f(6)),f(9));
Do m=2 By 1;
ma=a*m;
mb=b*m;
mc=c*m; /* gen non-primitives. */
If ma+mb+mc>n Then
Leave;
/* is this multiple a triple ? */
trips=trips+1; /* yuppers, then we found another.*/
If mod(m,2)=1 Then /* store as even multiple. */
call mems(mabce);
Put Edit(ma,mb,mc,' * ',
right(ma**2+mb**2,5),right(mc**2,5),ma+mb+mc)
(Skip,f(4),2(f(5)),a,2(f(6)),f(9));
End; /* m */
End; /* c */
End; /* b */
End; /* a */
Put Edit('max perimeter = ',n, /* show a single line of output. */
'Pythagorean triples =',trips,
'primitives =',prims)
(Skip,a,f(5),2(x(9),a,f(4)));
mems: Proc(e);
Dcl e Char(12);
memn+=1;
mabca(memn)=e;
End;
mema: Proc(e) Returns(bit(1));
Dcl e Char(12);
Do memi=1 To memn;
If mabca(memi)=e Then Return('1'b);
End;
Return('0'b);
End;
End;
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#Pascal
|
Pascal
|
if true then
begin
halt
end
|
http://rosettacode.org/wiki/Program_termination
|
Program termination
|
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks, etc.).
Unless otherwise described, no special cleanup outside that provided by the operating system is provided.
|
#Perl
|
Perl
|
if ($problem) {
exit integerErrorCode;
# conventionally, error code 0 is the code for "OK"
# (you can also omit the argument in this case)
# while anything else is an actual problem
}
|
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem
|
Primality by Wilson's theorem
|
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
|
#Go
|
Go
|
package main
import (
"fmt"
"math/big"
)
var (
zero = big.NewInt(0)
one = big.NewInt(1)
prev = big.NewInt(factorial(20))
)
// Only usable for n <= 20.
func factorial(n int64) int64 {
res := int64(1)
for k := n; k > 1; k-- {
res *= k
}
return res
}
// If memo == true, stores previous sequential
// factorial calculation for odd n > 21.
func wilson(n int64, memo bool) bool {
if n <= 1 || (n%2 == 0 && n != 2) {
return false
}
if n <= 21 {
return (factorial(n-1)+1)%n == 0
}
b := big.NewInt(n)
r := big.NewInt(0)
z := big.NewInt(0)
if !memo {
z.MulRange(2, n-1) // computes factorial from scratch
} else {
prev.Mul(prev, r.MulRange(n-2, n-1)) // uses previous calculation
z.Set(prev)
}
z.Add(z, one)
return r.Rem(z, b).Cmp(zero) == 0
}
func main() {
numbers := []int64{2, 3, 9, 15, 29, 37, 47, 57, 67, 77, 87, 97, 237, 409, 659}
fmt.Println(" n prime")
fmt.Println("--- -----")
for _, n := range numbers {
fmt.Printf("%3d %t\n", n, wilson(n, false))
}
// sequential memoized calculation
fmt.Println("\nThe first 120 prime numbers are:")
for i, count := int64(2), 0; count < 1015; i += 2 {
if wilson(i, true) {
count++
if count <= 120 {
fmt.Printf("%3d ", i)
if count%20 == 0 {
fmt.Println()
}
} else if count >= 1000 {
if count == 1000 {
fmt.Println("\nThe 1,000th to 1,015th prime numbers are:")
}
fmt.Printf("%4d ", i)
}
}
if i == 2 {
i--
}
}
fmt.Println()
}
|
http://rosettacode.org/wiki/Prime_conspiracy
|
Prime conspiracy
|
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of
the primes that immediately follow them.
and
This conspiracy among prime numbers seems, at first glance, to violate a
longstanding assumption in number theory: that prime numbers behave much
like random numbers.
─── (original authors from Stanford University):
─── Kannan Soundararajan and Robert Lemke Oliver
The task is to check this assertion, modulo 10.
Lets call i -> j a transition if i is the last decimal digit of a prime, and j the last decimal digit of the following prime.
Task
Considering the first one million primes. Count, for any pair of successive primes, the number of transitions i -> j and print them along with their relative frequency, sorted by i .
You can see that, for a given i , frequencies are not evenly distributed.
Observation
(Modulo 10), primes whose last digit is 9 "prefer" the digit 1 to the digit 9, as its following prime.
Extra credit
Do the same for one hundred million primes.
Example for 10,000 primes
10000 first primes. Transitions prime % 10 → next-prime % 10.
1 → 1 count: 365 frequency: 3.65 %
1 → 3 count: 833 frequency: 8.33 %
1 → 7 count: 889 frequency: 8.89 %
1 → 9 count: 397 frequency: 3.97 %
2 → 3 count: 1 frequency: 0.01 %
3 → 1 count: 529 frequency: 5.29 %
3 → 3 count: 324 frequency: 3.24 %
3 → 5 count: 1 frequency: 0.01 %
3 → 7 count: 754 frequency: 7.54 %
3 → 9 count: 907 frequency: 9.07 %
5 → 7 count: 1 frequency: 0.01 %
7 → 1 count: 655 frequency: 6.55 %
7 → 3 count: 722 frequency: 7.22 %
7 → 7 count: 323 frequency: 3.23 %
7 → 9 count: 808 frequency: 8.08 %
9 → 1 count: 935 frequency: 9.35 %
9 → 3 count: 635 frequency: 6.35 %
9 → 7 count: 541 frequency: 5.41 %
9 → 9 count: 379 frequency: 3.79 %
|
#PARI.2FGP
|
PARI/GP
|
conspiracy(maxx)={
print("primes considered= ",maxx);
x=matrix(9,9);cnt=0;p=2;q=2%10;
while(cnt<=maxx,
cnt+=1;
m=q;
p=nextprime(p+1);
q= p%10;
x[m,q]+=1);
print (2," to ",3, " count: ",x[2,3]," freq ", 100./cnt," %" );
forstep(i=1,9,2,
forstep(j=1,9,2,
if( x[i,j]<1,continue);
print (i," to ",j, " count: ",x[i,j]," freq ", 100.* x[i,j]/cnt," %" )));
print ("total transitions= ",cnt);
print(p);
}
|
http://rosettacode.org/wiki/Prime_decomposition
|
Prime decomposition
|
The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the prime decomposition of a given number
n
{\displaystyle n}
greater than 1.
If your language does not have an isPrime-like function available,
you may assume that you have a function which determines
whether a number is prime (note its name before your code).
If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes.
Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc).
Related tasks
count in factors
factors of an integer
Sieve of Eratosthenes
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
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#AWK
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AWK
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# Usage: awk -f primefac.awk
function pfac(n, r, f){
r = ""; f = 2
while (f <= n) {
while(!(n % f)) {
n = n / f
r = r " " f
}
f = f + 2 - (f == 2)
}
return r
}
# For each line of input, print the prime factors.
{ print pfac($1) }
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