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.print(s.substring(0, k));
			System.out.println("...");
		}
        return;
	}
}
/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