StringsA and B are K-similar (for some non-negative integer K) if we can swap the positions of two letters in A exactly Ktimes so that the resulting string equals B.
Given two anagrams A and B, return the smallest Kfor which A and B are K-similar.
Example 1:
Input: A = "ab", B = "ba"
Output: 1
Example 2:
Input: A = "abc", B = "bca"
Output: 2
Example 3:
Input: A = "abac", B = "baca"
Output: 2
Example 4:
Input: A = "aabc", B = "abca"
Output: 2
Note:
- 1 <= A.length == B.length <= 20
- A and B contain only lowercase letters from the set {'a', 'b', 'c', 'd', 'e', 'f'}
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