#include <iostream> #include <algorithm> using namespace std; string s[22]; bool cmp(string x,string y) { return x+y<y+x; } int main() { int n; cin>>n; for(int i = 1;i <= n;i++) { cin>>s[i]; } sort(s+1,s+n+1,cmp); for(int i = n;i >= 1;i--) { for(int j = 0;j < s[i].size();j++) { cout<<s[i][j]; } } return 0; }