Generate Login

Generate Login

The preferred way to generate user login in Polygon is to concatenate a prefix of the user's first name and a prefix of their last name, in that order. Each prefix must be non-empty, and any of the prefixes can be the full name. Typically there are multiple possible logins for each person.

You are given the first and the last name of a user. Return the alphabetically earliest login they can get (regardless of other potential Polygon users).

As a reminder, a prefix of a string s is its substring which occurs at the beginning of s: "a", "ab", "abc" etc. are prefixes of string "{abcdef}" but "b" and 'bc" are not. A string a is alphabetically earlier than a string b, if a is a prefix of b, or a and b coincide up to some position, and then a has a letter that is alphabetically earlier than the corresponding letter in b: "a" and "ab" are alphabetically earlier than "ac" but "b" and "ba" are alphabetically later than "ac".

Input

The input consists of a single line containing two space-separated strings: the first and the last names. Each character of each string is a lowercase English letter. The length of each string is between 1 and 10, inclusive.

Output

Output a single string — alphabetically earliest possible login formed from these names. The output should be given in lowercase as well.

Examples

Input

harry potter

Output

hap

Input

tom riddle

Output

tomr

思路：

两层for循环，运用string中的 substr函数解决即可

code:

#include <iostream>
#include <cstdio>
#include <cstring>
#include <string>
using namespace std;
int main(){
    string ans = "zzzzzzzzzzz";
    string a,b;
    cin >> a >> b;
    for(int i = 1; i <= a.length(); i++){
        for(int j = 1; j <= b.length(); j++){
            string tmp = a.substr(0,i) + b.substr(0,j);
            ans = min(ans,tmp);
        }
    }
    cout << ans << endl;
    return 0;
}