import java.util.*;

class Main {
    public static void main(String[] args) {
      Scanner sc = new Scanner(System.in);
      int cnt = sc.nextInt();
      String str = sc.next();
	  //Sの長さを求める
      int len = str.length();
      if(len <= cnt)
      {
      	 System.out.println(str);
      }
      else
      {
      	String new_str = str.substring(0, cnt);
        new_str += "...";
        System.out.println(new_str);
      
      }
    }
}
/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