
import java.io.*;
import java.util.*;
public class Main {
	public static void main(String[] args) throws Exception{
		// TODO Auto-generated method stub
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String s=br.readLine();
		int k=Integer.valueOf(s);
		s=br.readLine();
		int n=s.length();
		if(n<=k)
			System.out.println(s);
		else
		{
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		}
	}

} import java.io.*; io.* java import java.util.*; util.* java public class Main {
	public static void main(String[] args) throws Exception{
		// TODO Auto-generated method stub
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String s=br.readLine();
		int k=Integer.valueOf(s);
		s=br.readLine();
		int n=s.length();
		if(n<=k)
			System.out.println(s);
		else
		{
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		}
	}

} Main public static void main(String[] args) throws Exception{
		// TODO Auto-generated method stub
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String s=br.readLine();
		int k=Integer.valueOf(s);
		s=br.readLine();
		int n=s.length();
		if(n<=k)
			System.out.println(s);
		else
		{
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		}
	} main {
		// TODO Auto-generated method stub
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String s=br.readLine();
		int k=Integer.valueOf(s);
		s=br.readLine();
		int n=s.length();
		if(n<=k)
			System.out.println(s);
		else
		{
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		}
	} BufferedReader br=new BufferedReader(new InputStreamReader(System.in)); br new BufferedReader(new InputStreamReader(System.in)) String s=br.readLine(); s br.readLine() br.readLine br int k=Integer.valueOf(s); k Integer.valueOf(s) Integer.valueOf Integer s s=br.readLine() s br.readLine() br.readLine br int n=s.length(); n s.length() s.length s if(n<=k)
			System.out.println(s);
		else
		{
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		} n<=k n k System.out.println(s) System.out.println System.out System System.out s {
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		} String t=s.substring(0,k); t s.substring(0,k) s.substring s 0 k t=t+"..." t t+"..." t "..." System.out.println(t) System.out.println System.out System System.out t String[] args args public class Main {
	public static void main(String[] args) throws Exception{
		// TODO Auto-generated method stub
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String s=br.readLine();
		int k=Integer.valueOf(s);
		s=br.readLine();
		int n=s.length();
		if(n<=k)
			System.out.println(s);
		else
		{
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		}
	}

} public class Main {
	public static void main(String[] args) throws Exception{
		// TODO Auto-generated method stub
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String s=br.readLine();
		int k=Integer.valueOf(s);
		s=br.readLine();
		int n=s.length();
		if(n<=k)
			System.out.println(s);
		else
		{
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		}
	}

} Main

import java.io.*;
import java.util.*;
public class Main {
	public static void main(String[] args) throws Exception{
		// TODO Auto-generated method stub
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String s=br.readLine();
		int k=Integer.valueOf(s);
		s=br.readLine();
		int n=s.length();
		if(n<=k)
			System.out.println(s);
		else
		{
			String t=s.substring(0,k);
			t=t+"...";
			System.out.println(t);
		}
	}

}
