C. The Smallest String Concatenation

C. The Smallest String Concatenation
time limit per test
3 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

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.

Examples
Input
4
abba
abacaba
bcd
er
Output
abacabaabbabcder
Input
5
x
xx
xxa
xxaa
xxaaa
Output
xxaaaxxaaxxaxxx
Input
3
c
cb
cba
Output

cbacbc

字符串排序

#include <bits/stdc++.h>
using namespace std;

typedef long long int llint;
const int maxn = 5e4+100;
string a[maxn];

int cmp(const string &a, const string &b) {
	return a + b < b + a;
}

int main() {
	int n;
	scanf("%d",&n);
	for (int i = 0; i<n; i++)	cin >> a[i];
	sort(a, a+n, cmp);
	for (int i = 0; i<n; i++)	cout << a[i];
	cout << endl;
	return 0;
}


posted @ 2016-04-12 19:19  Tovi  阅读(210)  评论(0编辑  收藏  举报