Itertools.permutations() (Python 3)
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# Itertools.permutations() (Python 3)

• This tool returns successive r length permutations of elements in an iterable.
• If r is not specified or is None, then r defaults to the length of the iterable, and all possible full length permutations are generated.
• Permutations are printed in a lexicographic sorted order. So, if the input iterable is sorted, the permutation tuples will be produced in a sorted order.

• Sample Code
```1 2 3 4 5 6 7 8 9 10 11 12 >>> from itertools import permutations >>> print permutations(['1','2','3']) <itertools.permutations object at 0x02A45210> >>> >>> print list(permutations(['1','2','3'])) [('1', '2', '3'), ('1', '3', '2'), ('2', '1', '3'), ('2', '3', '1'), ('3', '1', '2'), ('3', '2', '1')] >>> >>> print list(permutations(['1','2','3'],2)) [('1', '2'), ('1', '3'), ('2', '1'), ('2', '3'), ('3', '1'), ('3', '2')] >>> >>> print list(permutations('abc',3)) [('a', 'b', 'c'), ('a', 'c', 'b'), ('b', 'a', 'c'), ('b', 'c', 'a'), ('c', 'a', 'b'), ('c', 'b', 'a')] ```
• You are given a string S.
• Your task is to print all possible permutations of size k of the string in lexicographic sorted order.
• Input Format
• A single line containing the space separated string s and the integer value k.
• Constraints
• 0 < k <= len(s)
• The string contains only UPPERCASE characters.
• Output Format
• Print the permutations of the string S on separate lines.

#### 문제풀이

• 단어s와 반복될 숫자n이 주어지면, 해당 단어를 n개의 조합으로 만들어서 출력하면됨
• n개의 조합은 itertools의 permutations를 사용하면 됨
• for문으로 해당 조합을 하나하나 뽑고, join을 이용하여 합침,
• 대신 s는 정렬이 되어있어야 해서 s를 sorted 시킨것을 출력함
```1 2 3 4 5 from itertools import permutations s , n = input().split() for i in list(permutations(sorted(s),int(n))): print(''.join(i)) ```
```1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 HACK 2 AC AH AK CA CH CK HA HC HK KA KC KH ```
```1 map(list,(permutations(s,int(i))) ```
```1 <map at 0x1c97d3d2808> ```
```1 ```