import java.util.Scanner;

public class Main{
	public static void main(String args[]){
		Scanner scan = new Scanner(System.in);
		int K = scan.nextInt();
		String S = scan.next();
		String result = null;

		if(S.length()>K) {
			result = S.substring(0,K)+"...";
		}else {
			result = S;
		}

		System.out.println(result);

	}
} import java.util.Scanner; Scanner 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();
		String result = null;

		if(S.length()>K) {
			result = S.substring(0,K)+"...";
		}else {
			result = S;
		}

		System.out.println(result);

	}
} Main public static void main(String args[]){
		Scanner scan = new Scanner(System.in);
		int K = scan.nextInt();
		String S = scan.next();
		String result = null;

		if(S.length()>K) {
			result = S.substring(0,K)+"...";
		}else {
			result = S;
		}

		System.out.println(result);

	} main {
		Scanner scan = new Scanner(System.in);
		int K = scan.nextInt();
		String S = scan.next();
		String result = null;

		if(S.length()>K) {
			result = S.substring(0,K)+"...";
		}else {
			result = S;
		}

		System.out.println(result);

	} Scanner scan = new Scanner(System.in); scan new Scanner(System.in) int K = scan.nextInt(); K scan.nextInt() scan.nextInt scan String S = scan.next(); S scan.next() scan.next scan String result = null; result null if(S.length()>K) {
			result = S.substring(0,K)+"...";
		}else {
			result = S;
		} S.length()>K S.length() S.length S K {
			result = S.substring(0,K)+"...";
		} result = S.substring(0,K)+"..." result S.substring(0,K)+"..." S.substring(0,K) S.substring S 0 K "..." {
			result = S;
		} result = S result S System.out.println(result) System.out.println System.out System System.out result String args[] args public class Main{
	public static void main(String args[]){
		Scanner scan = new Scanner(System.in);
		int K = scan.nextInt();
		String S = scan.next();
		String result = null;

		if(S.length()>K) {
			result = S.substring(0,K)+"...";
		}else {
			result = S;
		}

		System.out.println(result);

	}
} public class Main{
	public static void main(String args[]){
		Scanner scan = new Scanner(System.in);
		int K = scan.nextInt();
		String S = scan.next();
		String result = null;

		if(S.length()>K) {
			result = S.substring(0,K)+"...";
		}else {
			result = S;
		}

		System.out.println(result);

	}
} Main
import java.util.Scanner;

public class Main{
	public static void main(String args[]){
		Scanner scan = new Scanner(System.in);
		int K = scan.nextInt();
		String S = scan.next();
		String result = null;

		if(S.length()>K) {
			result = S.substring(0,K)+"...";
		}else {
			result = S;
		}

		System.out.println(result);

	}
}