CodeForces 632C The Smallest String Concatenation

题意：给定几个串，问如何组合起来使得字典序最小

思路：直接排个序就搞定了

#include <cstdio>
#include <queue>
#include <cstring>
#include <iostream>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <map>
#include <string>
#include <set>
#include <ctime>
#include <cmath>
#include <cctype>
using namespace std;
const int maxn = 50000+1000;
#define LL long long
int cas=1,T;
string s[maxn];
bool cmp(string a,string b)
{
string aa = a+b;
string bb = b+a;
return aa<bb;
}
int main()
{
int n;
scanf("%d",&n);
for (int i = 0;i<n;i++)
cin >> s[i];
sort(s,s+n,cmp);
for (int i = 0;i<n;i++)
cout << s[i];
cout << endl;
//freopen("in","r",stdin);
//scanf("%d",&T);
//printf("time=%.3lf",(double)clock()/CLOCKS_PER_SEC);
return 0;
}

Description

You're given a list of n strings a1, a2, ..., an.
You'd like to concatenate them together in some order such that the resulting string would be lexicographically smallest.

Given the list of strings, output the lexicographically smallest concatenation.

Input

The first line contains integer n — the number of strings (1 ≤ n ≤ 5·104).

Each of the next n lines contains one string ai (1 ≤ |ai| ≤ 50)
consisting of only lowercase English letters. The sum of string lengths will not exceed 5·104.

Output

Print the only string a — the lexicographically smallest string concatenation.

Sample Input

Input

4
abba
abacaba
bcd
er

Output

abacabaabbabcder

Input

5
x
xx
xxa
xxaa
xxaaa

Output

xxaaaxxaaxxaxxx

Input

3
c
cb
cba

Output

cbacbc