#include <bits/stdc++.h>
int main() {
  int n, count = 0;
  char str[1000];
  scanf("%d", &n);
  scanf("%s", str);
  for (int i = 0; str[i] != '\0'; i++) count++;
  if (count <= n)
    puts(str);
  else {
    for (int i = 0; i < n; i++) printf("%c", str[i]);
    printf("...");
  }
  return 0;
}
