Description
You are given an array A of strings.
A move onto S consists of swapping any two even indexed characters of S, or any two odd indexed characters of S.
Two strings S and T are special-equivalent if after any number of moves onto S, S == T.
For example, S = “zzxy” and T = “xyzz” are special-equivalent because we may make the moves “zzxy” -> “xzzy” -> “xyzz” that swap S[0] and S[2], then S[1] and S[3].
Now, a group of special-equivalent strings from A is a non-empty subset of A such that:
- Every pair of strings in the group are special equivalent, and;
- The group is the largest size possible (ie., there isn’t a string S not in the group such that S is special equivalent to every string in the group)
Return the number of groups of special-equivalent strings from A.
Example 1:
Example 2:
Note:
- 1 <= A.length <= 1000
- 1 <= A[i].length <= 20
- All A[i] have the same length.
- All A[i] consist of only lowercase letters.
分析
题目的意思是:分类特别相等的字符串,这道题我看了好多遍没看明白,后面发现是奇数位置和偶数位置排序后构成的数相等才算相等,所以这里用一个set集合来统计一下个数就行了。如果看懂题目才好做,否则估计跟我一样郁闷了,哈哈哈。
代码
参考文献
[LeetCode] Python O(n * k lg k) sol. by signature. 90%+ [w/ Hint]