lc567. Permutation in String

567. Permutation in String Medium

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Share 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

思路：活动窗口

代码：python3

class Solution:
    def checkInclusion(self, s1: str, s2: str) -> bool:
        m=len(s1)
        n=len(s2)
        if m>n:return False
        s1hash=[0]*123
        s2hash=[0]*123
        for x in s1:
            s1hash[ord(x)]+=1
        for i in range(0,n):
            s2hash[ord(s2[i])]+=1
            if i>=m:
                s2hash[ord(s2[i-m])]-=1
            if s2hash==s1hash:
                return True
        return False
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转载于:https://juejin.im/post/5d0c3bcee51d4510803ce3cb