simple 最长公共前缀

题目

编写一个函数来查找字符串数组中的最长公共前缀。
如果不存在公共前缀，返回空字符串 “”。

示例 1:
输入: ["flower","flow","flight"]
输出: "fl"

示例 2:
输入: ["dog","racecar","car"]
输出: ""
解释: 输入不存在公共前缀。

说明:
所有输入只包含小写字母 a-z 。

#cpp
class Solution {
public:
    string longestCommonPrefix(vector<string>& strs) {
        int n = strs.size();
        if(n == 0) return "";
        if(n == 1) return strs[0];
        sort(strs.begin(),strs.end());
        for(int i = 0;i < min(strs[0].length(),strs[n-1].length());i++){
            if(strs[0][i] != strs[n-1][i]) 
                return strs[0].substr(0,i);
        }
        return strs[0];
    }
};

补充知识点

c++ vertor sort
先从第一个字符比较，然后比较第二个，一次类推，和字符长度基本无关

#include <iostream>
#include <vector>

using namespace std;

int main() {

    vector <string> words = {"the", "quick", "red", "fox", "jumps", "over", "the", "slow", "red", "turtle"};
    sort(words.begin(), words.end());
    for (vector<string>::iterator it = words.begin(); it != words.end(); it++){
        cout << *it << endl;
    }
    return 0;
}

输出

/Users/zhangjiabin/Documents/cpp/cpp/yufa/vectorStringSort/cmake-build-debug/vectorStringSort
fox
jumps
over
quick
red
red
slow
the
the
turtle

Process finished with exit code 0