[leetcode] 最长公共前缀 简单水题模拟

class Solution {
public:
    bool check(vector<string>& strs, string temp, int len){
        int flag = 0;
        for(int i = 1;i < strs.size();i ++) {
            if(strs[i].substr(0,len) != temp) {
                flag = 1;
                break;
            }
        }
        return flag;
    }
    string longestCommonPrefix(vector<string>& strs) {
        int n = strs.size();
        int miniLen = 2000;
        string nul = "";
        for(int i = 0;i < n;i ++) {
            miniLen = min(miniLen, (int)strs[i].size());
        }
        int l = 0,r = miniLen + 1;
        while(l < r) {
            int len = (l + r) / 2;
            string temp = strs[0].substr(0,len);
            int flag = check(strs, temp, len);
            if(flag) r = len;
            else l = len + 1;
        }
        if(check(strs, strs[0].substr(0,l), l)) -- l;
        return strs[0].substr(0,l);
    }
};