Codeforces 632C The Smallest String Concatenation 【string】

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

4abbaabacababcder

output

abacabaabbabcder

input

5xxxxxaxxaaxxaaa

output

xxaaaxxaaxxaxxx

input

3ccbcba

output

cbacbc

题意：给你n个短串，让你组成一个字典序最小的串。

思路：string随便搞。

AC代码：

#include <iostream>#include <cstdio>#include <cstring>#include <cmath>#include <algorithm>#include <map>#include <string>#include <vector>#include <queue>#include <stack>#define CLR(a, b) memset(a, (b), sizeof(a))#define ll o<<1#define rr o<<1|1using namespace std;typedef long long LL;const int MOD = 1e9+7;const int MAXN = 5*1e4+10;const int INF = 0x3f3f3f3f;void add(LL &x, LL y) {x += y; x %= MOD;}string str[MAXN];bool cmp(string a, string b){    return a + b < b + a;}int main(){    int n; cin >> n;    for(int i = 0; i < n; i++) cin >> str[i];    sort(str, str+n, cmp);    for(int i = 0; i < n; i++) cout << str[i];    cout << endl;    return 0;}