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 max = -1001001001;
		int min = 1001001001;
		for(int i = 0 ; i < n ; i++) {
			int data = sc.nextInt();
			max = Math.max(max, data);
			min = Math.min(min, data);
		}
		System.out.println(max - min);
 	}
}