#include<bits/stdc++.h> using namespace std; bool x(string a,string b){ return a+b>b+a; } int main(){ //freopen("bignum.in","r",stdin); //freopen("bignum.out","w",stdout); int n;cin>>n; string s[105]; for(int i=0;i<n;i++) cin>>s[i]; sort(s,s+n,x); for(int i=0;i<n;i++) cout<<s[i]; //fclose(stdin); //fclose(stdout); }