【leetcode】3.Longest Substring Without Repeating Characters

 Question

Given a string, find the length of the longest substring without repeating characters.

Example

Given "abcabcbb" , the answer is"abc", which the length is 3.

Given "bbbb", 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.

Solution

public class Solution {  
    public int lengthOfLongestSubstring(String s) {  
        if(s.length()<=1){                                          //如果字符串长度为0或1，返回其长度
            return s.length();  
        } 
        String temp=s.substring(0,1);                               //截取字符串s的第一个字符
        int max=1;  
  
        for(int i=1;i