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

int main(void){
  int a=0;
  scanf("%d",&a);
  char s[999]="";
  scanf("%s",s);
  int y = strlen(s);
  //printf("a is %d\n",a);
  //printf("len is %d\n",y);
  if (y<=a){
    printf("%s",s);
  }else{
    char t[999]=" ";
    strncpy(t,s,a);
    printf("%s",t);
    printf("...");
  }
  return 0;
}
