import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ

		Scanner scanner = new Scanner(System.in);

		//入力表示
		int K = scanner.nextInt();
		String S = scanner.next();
		int num = S.length();
		
		String x ="";
		
		if (num <= 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