import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main{

	public static void main(String[] args) throws IOException {

		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		int n = Integer.parseInt(br.readLine());
		String k = br.readLine();

		String ans;
		if(n >= k.length()) {

			ans = k;
		}else {

			ans = k.substring(0, n ) + "...";
		}

		System.out.println(ans);

	}
}

/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