题解 | #最长公共前缀#记录

#include <queue>
class Solution {
  public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     *
     * @param strs string字符串vector
     * @return string字符串
     */
    string merge(string s1, string s2) {
        string ans = "";
        if (s1.empty() || s2.empty()) return ans;
        else if (s1 == s2) return s1;
        for (int i = 0; i < s1.size() && i < s2.size(); i++) {
            if (s1[i] == s2[i]) {
                ans += s1[i];
            } else {
                break;
            }
        }
        return ans;
    }
    string mergePre(vector<string>& strs, int b, int e) {

        if (b < e) {
            int mid = (b + e) / 2;
            return merge(mergePre(strs, b, mid), mergePre(strs, mid + 1, e));
        }
        else if(b==e){
            return strs[b];
        }
        else
            return nullptr;

    }
    string longestCommonPrefix(vector<string>& strs) {
        // write code here
        //归并
        if(strs.empty()) return "";
        return mergePre(strs, 0, strs.size() - 1);
    }
};