leetcode 3. Longest Substring Without Repeating Characters---最长不重复子串 C语言版 faster 100%

int lengthOfLongestSubstring(char* s) {
    int max = 0;
    int i = 0,j,k;
    int n = strlen(s);
    if(n == 0 || n == 1)
        return n;
    for(i = 0; s[i]; i++) {
       for(j = i+1; s[j]; j++) {
          for(k = j - 1; k >= i; k--) {
               if(s[j] == s[k]) {
                if(max < j - i)
                    max = j - i
                break;
            }
         }
    }
    return max;
}

int lengthOfLongestSubstring(char* s) {
    int max = 0;
    int i = 0,j,k;
    int n = strlen(s);
    if(n == 0 || n == 1)
        return n;
    for(j = i+1; s[j]; j++) {
        for(k = j - 1; k >= i; k--) {
            if(s[j] == s[k]) {
                i = k + 1;
                if(max >= n - i)
                    return max;
                break;
            }
         }
         if(max < j - i + 1)
             max = j - i + 1;
    }
    return max;
}