import java.util.*;

public class Main {

    public static void main(String args[]) {


        Scanner scan = new Scanner(System.in);

        int k = scan.nextInt();
        String s = scan.next();

        if (s.length() <= k) {
            System.out.println(s);
        } else {
            String n = s.substring(0, k).concat("...");
            System.out.println(n);
        }

    }


}
/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