14. Longest Common Prefix

题目地址

dd注意判空

class Solution {public:    string longestCommonPrefix(vector<string> &strs) {        string ans = "";        if (strs.size() == 0) return ans;        int len = strs[0].size();        for (int i = 0; i < strs.size(); i++) {            if (i) {                if (strs[i].size() < len) len = strs[i].size();            }        }        bool flag = 1;        for (int i = 0; i < len; i++) {            for (int j = 1; j < strs.size(); j++) {                if (strs[j][i] != strs[0][i]) {                    flag = 0;                    break;                }            }            if (flag) ans += strs[0][i];            else break;        }        return ans;    }};