# Numbers of length N and value less than K

Gowtham Ghaandhi M Oct 04 2020 · 1 min read

Conditions on Input
1. List A is not empty
2. Elements of list A must be digits between 0 and 9
3. The value of B must be a digit from 0 and 9
4. The Value of C must be a positive integer.
5. Number of digits in C must be greater than or equal to the value of B

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Solution

class Solution:
# @param A : list of integers
# @param B : integer
# @param C : integer
# @return an integer
def __init__(self, A, B, C):
self.A=list(set(A))  # Makes distinct elements in list A
self.B=B
self.C=C
def solve(self):
if self.A==[]:
elif self.A!=[]:
for i in self.A:
if not(0<=i<9):
raise Exception("Please provide the values in the list(A) are only digits from 0 to 9")
elif not(0<=self.B<=9):
raise Exception("Please provide the values of B are only digits from 0 to 9")
elif self.C<=0:
raise Exception("Please provide the values of B are only digits from 0 to 9")

from itertools import combinations_with_replacement
comb = combinations_with_replacement(self.A*2, self.B)
List = []
for i in list(comb):
str_num=""
for j in range(self.B):
str_num = str_num+str(i[j])
if len(str_num)>1:
if str_num[0]!='0' and int(str_num)<self.C:
List.append(int(str_num))
elif int(str_num)<self.C:
List.append(int(str_num))

print(sorted(list(set(List))))

Testing

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Input_1

sol = Solution([0, 1, 5], 1, 2)
sol.solve()

Output_1
[0, 1]

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Input_2

sol = Solution([0, 1, 2, 5], 2, 21)
sol.solve()

Output_2
[10, 11, 12, 15, 20]

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Input_3

sol = Solution([0, 1, 2, 5, 7], 3, 500)
sol.solve()

Output_3
[100, 101, 102, 105, 107, 110, 111, 112, 115, 117, 120, 121, 122, 125, 127, 150, 151, 152, 155, 157, 170, 171, 172, 175, 177, 200, 201, 202, 205, 207, 211, 212, 215, 217, 220, 221, 222, 225, 227, 250, 251, 252, 255, 257, 270, 271, 272, 275, 277]

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* * *
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