Given a string, find the length of the longest substring without repeating characters.
Examples:
Given "abcabcbb"
, the answer is "abc"
, which the length is 3.
Given "bbbbb"
, the answer is "b"
, with the length of 1.
Given "pwwkew"
, the answer is "wke"
, with the length of 3. Note that the answer must be a substring, "pwke"
is a subsequence and not a substring.
class Solution { public: int lengthOfLongestSubstring(string s) { int count=0; vector<int> table(128,-1); //要利用j将起始位置更新到第一次出现重复的位置。 int j=0; for(int i=0;i<s.size();i++) { if(table[s[i]]!=-1) { while(j<=table[s[i]]) table[s[j++]]=-1; } count=max(count,i-j+1); table[s[i]]=i; } return count; } };