package m.shin;
import java.util.Arrays;
import java.util.Scanner;
public class Con21 {

	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		int N = s.nextInt() , K = s.nextInt();
		int[] n = new int[N];
		for(int i = 0;i < N;i++){
			n[i] = s.nextInt();
		}
		s.close();

		Arrays.sort(n);
		System.out.println(n[N-1] - n[0]);

	}

}