【LeetCode014】 Longest Common Prefix

#include <iostream>
#include <string>
#include <vector>
using namespace std;

class Solution {
public:
    string longestCommonPrefix(vector<string>& strs) {
        if(strs.size() == 0) 
            return "";
        char c;
        for(int i = 0; i < strs[0].length(); ++i){  //length()与size()
            c = strs[0][i];
            for(int j = 1; j < strs.size(); ++j){  //纵向比较
                if(strs[j].length() == i || strs[j][i] != c)  
                //i已经是第j个字符串的长度或者不相等
                    return strs[0].substr(0, i);  //不包括i，substr()而不是substring()
            }
        }
        return strs[0];  //strs[0]遍历完成
    }
};

int main()
{
    string s1 = "ABCD";
    string s2 = "ABCF";
    string s3 = "ABCR";
    vector<string> array;
    array.push_back(s1);
    array.push_back(s2);
    array.push_back(s3);
    Solution sol;
    string answer(sol.longestCommonPrefix(array));
    for(int i = 0; i < answer.size(); ++i){
        cout << answer[i];}
    cout << endl;
    return 0;

参考：https://www.jianshu.com/p/63dcc0d7db75