import java.util.Scanner;
public class Main {


    public static void main(String[] args) {


        Scanner scan = new Scanner(System.in);
        int N=scan.nextInt();

        String M=scan.next();

      if(M.length()<=N){System.out.println(M);}
      else{
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      }
    }

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


    public static void main(String[] args) {


        Scanner scan = new Scanner(System.in);
        int N=scan.nextInt();

        String M=scan.next();

      if(M.length()<=N){System.out.println(M);}
      else{
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      }
    }

} Main public static void main(String[] args) {


        Scanner scan = new Scanner(System.in);
        int N=scan.nextInt();

        String M=scan.next();

      if(M.length()<=N){System.out.println(M);}
      else{
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      }
    } main {


        Scanner scan = new Scanner(System.in);
        int N=scan.nextInt();

        String M=scan.next();

      if(M.length()<=N){System.out.println(M);}
      else{
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      }
    } Scanner scan = new Scanner(System.in); scan new Scanner(System.in) int N=scan.nextInt(); N scan.nextInt() scan.nextInt scan String M=scan.next(); M scan.next() scan.next scan if(M.length()<=N){System.out.println(M);}
      else{
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      } M.length()<=N M.length() M.length M N {System.out.println(M);} System.out.println(M) System.out.println System.out System System.out M {
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      } String Ns=M.substring(0,N); Ns M.substring(0,N) M.substring M 0 N System.out.println(Ns+"...") System.out.println System.out System System.out Ns+"..." Ns "..." String[] args args public class Main {


    public static void main(String[] args) {


        Scanner scan = new Scanner(System.in);
        int N=scan.nextInt();

        String M=scan.next();

      if(M.length()<=N){System.out.println(M);}
      else{
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      }
    }

} public class Main {


    public static void main(String[] args) {


        Scanner scan = new Scanner(System.in);
        int N=scan.nextInt();

        String M=scan.next();

      if(M.length()<=N){System.out.println(M);}
      else{
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      }
    }

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


    public static void main(String[] args) {


        Scanner scan = new Scanner(System.in);
        int N=scan.nextInt();

        String M=scan.next();

      if(M.length()<=N){System.out.println(M);}
      else{
          String Ns=M.substring(0,N);
          System.out.println(Ns+"...");
      }
    }

}

