import java.util.*;
class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int K = sc.nextInt();
    StringBuilder sb = new StringBuilder(sc.next());
    if(sb.length() <= K){
      System.out.print(sb.toString());
    }else{
      System.out.print(sb.substring(0, K).toString() + "...");
    }
  }
} import java.util.*; util.* java class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int K = sc.nextInt();
    StringBuilder sb = new StringBuilder(sc.next());
    if(sb.length() <= K){
      System.out.print(sb.toString());
    }else{
      System.out.print(sb.substring(0, K).toString() + "...");
    }
  }
} Main public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int K = sc.nextInt();
    StringBuilder sb = new StringBuilder(sc.next());
    if(sb.length() <= K){
      System.out.print(sb.toString());
    }else{
      System.out.print(sb.substring(0, K).toString() + "...");
    }
  } main {
    Scanner sc = new Scanner(System.in);
    int K = sc.nextInt();
    StringBuilder sb = new StringBuilder(sc.next());
    if(sb.length() <= K){
      System.out.print(sb.toString());
    }else{
      System.out.print(sb.substring(0, K).toString() + "...");
    }
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int K = sc.nextInt(); K sc.nextInt() sc.nextInt sc StringBuilder sb = new StringBuilder(sc.next()); sb new StringBuilder(sc.next()) if(sb.length() <= K){
      System.out.print(sb.toString());
    }else{
      System.out.print(sb.substring(0, K).toString() + "...");
    } sb.length() <= K sb.length() sb.length sb K {
      System.out.print(sb.toString());
    } System.out.print(sb.toString()) System.out.print System.out System System.out sb.toString() sb.toString sb {
      System.out.print(sb.substring(0, K).toString() + "...");
    } System.out.print(sb.substring(0, K).toString() + "...") System.out.print System.out System System.out sb.substring(0, K).toString() + "..." sb.substring(0, K).toString() sb.substring(0, K).toString sb.substring(0, K) sb.substring sb 0 K "..." String[] args args
import java.util.*;
class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int K = sc.nextInt();
    StringBuilder sb = new StringBuilder(sc.next());
    if(sb.length() <= K){
      System.out.print(sb.toString());
    }else{
      System.out.print(sb.substring(0, K).toString() + "...");
    }
  }
}
