import java.util.*;
public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub

		
		Scanner b = new Scanner(System.in);
		
		int n = b.nextInt();
		String s = b.next();
		
		if(n >= s.length()) {
			System.out.println(s);
		}
		else{
			String f = s.substring(0, n);
			System.out.println(f + "...");
		}
	}

}

/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