import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int K = sc.nextInt();

		int[] n = new int[N];
		int min = 100000;
		int max = 0;

		for(int i=0; i<N; i++){
			n[i] = sc.nextInt();

			max = Math.max(max, n[i]);
			min = Math.min(min, n[i]);
		}
		sc.close();

		System.out.println(max-min);

	}

}