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"

 1 /**
 2  * @param {string} s
 3  * @return {number}
 4  */
 5 
 6 var lengthOfLongestSubstring = function(s) { 8     var len = s.length;
 9     var max = 0;
10     var temp = [];
11     
12     for(var i=0; i<len; i++) {
13         var index = temp.indexOf(s[i]);
 
14         if(index >= 0) {
15             if(temp.length > max) {
16                 // 記錄當前的長度
17                 max = temp.length;                       
18             }
19             // 截取重復字母以及之前的字母
20             temp.splice(0, index+1);    
21         }
22         
23         temp.push(s[i]);
 
24     }
25     
26     return max > temp.length ? max: temp.length;
27 };

就簡單的拿數組模擬一下思路就OK了。

Leetcode3---Longest Substring Without Repeating Characters