leetcode 567【medium】---Permutation in String
Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1.
In other words, one of the first string's permutations is the substring of the second string.
Example 1:
Input:s1 = "ab" s2 = "eidbaooo"
Output:True
Explanation: s2 contains one permutation of s1 ("ba").
Example 2:
Input:s1= "ab" s2 = "eidboaoo"
Output: False
Note:
- The input strings only contain lower case letters.
- The length of both given strings is in range [1, 10,000].
思路： 题意简单，不罗嗦。跟438题一摸一样的方法，比438还简单一些，但是难度比438高一级？
438链接：http://blog.****.net/fawnzou2017/article/details/78944776
