import java.util.Scanner;
import java.io.*;

class Main{
 public static void main(String args[]){
   Scanner sc = new Scanner(System.in);
   int k = sc.nextInt();
   String s = sc.next();
   
   
   if(s.length()<=k){
   	System.out.println(s);
   }
   else if(s.length()>k){
   	System.out.println(s.substring(0,k)+"...");
   }
 
 }
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz