int lengthOfLongestSubstring(char* s){
    int len = strlen(s);
    int apear[128];
    int max = 0;
    int tmp = 0;
    for(int i=0;i<128;i++)
    {
        apear[i] = -1;
    }
    for(int j=0;j<len;j++)
    {
        int i = apear[s[j]];
        apear[s[j]] = j;
        tmp = tmp < j-i ? tmp+1 : j-i;
        max = max > tmp ? max : tmp;
    }
    return max;
}