itertools.combinations_with_replacement(iterable, r)

This tool returns $\textbf{r}$ length subsequences of elements from the input iterable allowing individual elements to be repeated more than once.

Combinations are emitted in lexicographic sorted order. So, if the input iterable is sorted, the combination tuples will be produced in sorted order.

Sample Code

from itertools import combinations_with_replacement

print list(combinations_with_replacement('12345',2))
[('1', '1'), ('1', '2'), ('1', '3'), ('1', '4'), ('1', '5'), ('2', '2'), ('2', '3'), ('2', '4'), ('2', '5'), ('3', '3'), ('3', '4'), ('3', '5'), ('4', '4'), ('4', '5'), ('5', '5')]

A = [1,1,3,3,3]
print list(combinations(A,2))
[(1, 1), (1, 3), (1, 3), (1, 3), (1, 3), (1, 3), (1, 3), (3, 3), (3, 3), (3, 3)]

Task

You are given a string $\mbox{S}$.

Your task is to print all possible size $\boldsymbol{\mbox{k}}$ replacement combinations of the string in lexicographic sorted order.

Input Format

A single line containing the string $\mbox{S}$ and integer value $\boldsymbol{\mbox{k}}$ separated by a space.

Constraints

$0<k\leq len(S)$

The string contains only UPPERCASE characters.

Output Format

Print the combinations with their replacements of string $\mbox{S}$ on separate lines.

Sample Input
HACK 2

Sample Output
AA
AC
AH
AK
CC
CH
CK
HH
HK
KK

见题面

见题面