import java.util.Arrays;
import java.util.Scanner;

public class No21 {

    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 minAvg = nums[0];
        int maxAvg = nums[n - 1];

        System.out.println(maxAvg - minAvg);

        sc.close();
    }

}