LeetCode 3. Longest Substring Without Repeating Characters

public class Solution {
public int lengthOfLongestSubstring(String s) {
int[] counts = new int[128];//标记字符出现位置
for(int i = 0;i<counts.length;i++){
counts[i]=-1;//初始化
}
char []src = s.toCharArray();
int index = 0;
int max = 0;
for(int i = 0 ; i<src.length;i++){
if(counts[ src[i] ]<index){
counts[src[i]] = i;
max = Math.max(max,i-index+1);
}else{
index = counts[src[i]]+1;
counts[src[i]] = i;
}
}
return max;
}

}