import java.util.Scanner;

public class Main {

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

		int K = sc.nextInt();
		String S = sc.next();

		int A = S.length();

		if (A > K) {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} else {
			System.out.print(S);
		}
	}

} import java.util.Scanner; Scanner java.util public class Main {

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

		int K = sc.nextInt();
		String S = sc.next();

		int A = S.length();

		if (A > K) {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} else {
			System.out.print(S);
		}
	}

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

		int K = sc.nextInt();
		String S = sc.next();

		int A = S.length();

		if (A > K) {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} else {
			System.out.print(S);
		}
	} main {
		Scanner sc = new Scanner(System.in);

		int K = sc.nextInt();
		String S = sc.next();

		int A = S.length();

		if (A > K) {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} else {
			System.out.print(S);
		}
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int K = sc.nextInt(); K sc.nextInt() sc.nextInt sc String S = sc.next(); S sc.next() sc.next sc int A = S.length(); A S.length() S.length S if (A > K) {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} else {
			System.out.print(S);
		} A > K A K {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} String B = S.substring(0, K); B S.substring(0, K) S.substring S 0 K System.out.print(B + "...") System.out.print System.out System System.out B + "..." B "..." {
			System.out.print(S);
		} System.out.print(S) System.out.print System.out System System.out S String[] args args public class Main {

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

		int K = sc.nextInt();
		String S = sc.next();

		int A = S.length();

		if (A > K) {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} else {
			System.out.print(S);
		}
	}

} public class Main {

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

		int K = sc.nextInt();
		String S = sc.next();

		int A = S.length();

		if (A > K) {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} else {
			System.out.print(S);
		}
	}

} Main
import java.util.Scanner;

public class Main {

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

		int K = sc.nextInt();
		String S = sc.next();

		int A = S.length();

		if (A > K) {

			String B = S.substring(0, K);

			System.out.print(B + "...");
		} else {
			System.out.print(S);
		}
	}

}
