import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
       Scanner sc = new Scanner(System.in);
        String h = sc.nextLine();
        String s = sc.nextLine();
        int k = Integer.parseInt(h);
        int len = String.valueOf( s ).length();
        if (len <= k) {
            System.out.println(s);
        } else {
            for (int i = 0; i < k; i++) {
                System.out.print(s.charAt(i));
            }
            System.out.print("...");
        }
        
    }
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz