#include <stdio.h>
#include <string.h>

int main(void){
  int N = 0;
  int i = 0;

  char S[10][21] = {""};
  char hoge[210] = "";

  scanf("%d", &N);

  for(i=0;i<N;i++){
    scanf("%s",S[i]);
    strcat(hoge,S[i]);
  }

  printf("%s\n",hoge);

  return 0;
}