【leetCode】14_最长公共前缀

class Solution {
public:
    string longestCommonPrefix(vector& strs) {
        string ans;
        if (strs.size() == 0){
            return ans;
        }
        int i = 0;
        bool flag = true;
        while (flag){
            flag = true;
            int j;
            char c = 1;
            if (strs[0].size() > i){
                c = strs[0][i];
            }
            else
                flag = false;
            for (j = 1; j < strs.size() && flag; j ++){
                if (i < strs[j].length() && strs[j][i] == c){
                    continue;
                }
                flag = false;
            }
            if (flag)
                i ++;
        }
        ans = strs[0].substr(0, i);
        return ans;
    }
};