import java.util.Arrays;
import java.util.Scanner;

public class Main{
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int N = scan.nextInt();
		int K = scan.nextInt();
		int []n = new int [N];
		for(int i = 0; i < N; i++) {
			n[i] = scan.nextInt();
		}
		scan.close();
		Arrays.sort(n);
		int max = n[n.length - 1];
		int min = n[0];
		int ans = max - min;
		System.out.println(ans);

	}
}