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();
		
		if(s.length() <= k) {
			System.out.println(s);
			return;
		}
		
		String x = s.substring(0, k);

		System.out.println(x + "...");
	}
} 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();
		
		if(s.length() <= k) {
			System.out.println(s);
			return;
		}
		
		String x = s.substring(0, k);

		System.out.println(x + "...");
	}
} Main public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		
		int  k = sc.nextInt();
		String s =sc.next();
		
		if(s.length() <= k) {
			System.out.println(s);
			return;
		}
		
		String x = s.substring(0, k);

		System.out.println(x + "...");
	} main {

		Scanner sc = new Scanner(System.in);
		
		int  k = sc.nextInt();
		String s =sc.next();
		
		if(s.length() <= k) {
			System.out.println(s);
			return;
		}
		
		String x = s.substring(0, k);

		System.out.println(x + "...");
	} 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 if(s.length() <= k) {
			System.out.println(s);
			return;
		} s.length() <= k s.length() s.length s k {
			System.out.println(s);
			return;
		} System.out.println(s) System.out.println System.out System System.out s return; String x = s.substring(0, k); x s.substring(0, k) s.substring s 0 k System.out.println(x + "...") System.out.println System.out System System.out x + "..." x "..." 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();
		
		if(s.length() <= k) {
			System.out.println(s);
			return;
		}
		
		String x = s.substring(0, k);

		System.out.println(x + "...");
	}
} public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		
		int  k = sc.nextInt();
		String s =sc.next();
		
		if(s.length() <= k) {
			System.out.println(s);
			return;
		}
		
		String x = s.substring(0, k);

		System.out.println(x + "...");
	}
} 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();
		
		if(s.length() <= k) {
			System.out.println(s);
			return;
		}
		
		String x = s.substring(0, k);

		System.out.println(x + "...");
	}
}
