3.无重复字符的最长子串

题目

思路
1.字符串查找重复字符
2.有重复字符则处理重复字符之间的数据并记录长度
代码

int lengthOfLongestSubstring(char* s) {
    
    int maxlen = 0,currlen = 0;
    int table[128], i, j, start = 0;
    memset(table, 0, sizeof(table));
    
    for (i = 0; s[i] != '\0'; ++i){
        if( (++table[s[i]]) == 2 ){//判断重复
            if (currlen > maxlen){
                maxlen = currlen;//记录最长长度
            }
            for(j = start; j < i; ++j){ //*start记录重复的字符后一个位置
                if (s[j] == s[i]){
                    table[s[j]] = 1;
                    start = j+1;
                    break;
                }else{
                    //清空数组，重置记录长度
                    --currlen;
                    table[s[j]] = 0;
                }
            }
        }else{
            ++currlen;//无重复记录长度自加
        }
    }
    if (currlen > maxlen){
        maxlen = currlen;
    }
    return maxlen;
}