力扣3. 无重复字符的最长子串

Posted 2021-06-14 幽殇默

https://leetcode-cn.com/problems/longest-substring-without-repeating-characters/
双指针滑动窗口

class Solution {
public:
    int lengthOfLongestSubstring(string s) {
        int ans=0;
        map<char,int> mp;
        for(int i=0,j=0;i<s.size();i++)
	    {
		    mp[s[i]]++;
		    while(mp[s[i]]==2)
		    {
			    mp[s[j]]--;
			    j++;
		    }
		    ans=max(ans,i-j+1);
	    }
	    return ans;
    }
};