import java.util.*;

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);
        else
            System.out.println(S.substring(0,K) + "...");
    }
} import java.util.*; util.* java 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);
        else
            System.out.println(S.substring(0,K) + "...");
    }
} 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);
        else
            System.out.println(S.substring(0,K) + "...");
    } main {
        Scanner sc = new Scanner(System.in);
      	int K = sc.nextInt();
        String S = sc.next();
        if (S.length() <= K)
            System.out.println(S);
        else
            System.out.println(S.substring(0,K) + "...");
    } 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);
        else
            System.out.println(S.substring(0,K) + "..."); S.length() <= K S.length() S.length S K System.out.println(S) System.out.println System.out System System.out S System.out.println(S.substring(0,K) + "...") System.out.println System.out System System.out S.substring(0,K) + "..." S.substring(0,K) S.substring S 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();
        String S = sc.next();
        if (S.length() <= K)
            System.out.println(S);
        else
            System.out.println(S.substring(0,K) + "...");
    }
}