import java.util.Scanner;

public class Main {

    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        int K = scan.nextInt();

        Scanner scan2 = new Scanner(System.in);
        String S = scan.next();

        if (S.length()<=K ){
            System.out.println(S);
        }else{
            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