import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int k = Integer.parseInt(in.nextLine());
		String s = in.nextLine();
		if(s.length() > k) {
			String mod_s = s.substring(0,k) + "...";
			System.out.println(mod_s);
		} else {
			System.out.println(s);
		}
	}
}
/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