import java.util.Arrays;
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[] nums = new int[N];

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

        Arrays.sort(nums);

        int min = nums[0];
        int max = nums[N - 1];

        System.out.println(max - min);

    }

}