import java.util.Scanner;

public class Main{
	public static void main(String args[]){
		Scanner scan = new Scanner(System.in);

		int len = scan.nextInt();
		scan.nextLine();
		String topic = scan.nextLine();

		if(topic.length() <= len){
			System.out.println(topic);
		}else{
			System.out.println(topic.substring(0, len) + "...");
		}
		scan.close();
	}
}
/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