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 list[] = new int[n];
		for(int i=0; i<n; i++) {
			list[i] = scan.nextInt();
		}
		Arrays.sort(list);
		int ans = list[n-1] - list[0];
		System.out.println(ans);
	}
}