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


public class Main_yukicoder21 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int k = sc.nextInt();
        int[] nn = new int[n];
        for (int i = 0; i < n; i++) {
        	nn[i] = sc.nextInt();
        }
        Arrays.sort(nn);

        System.out.println(nn[n - 1] - nn[0]);

        sc.close();
    }
}