import java.util.*;

public class Main {
    private static Scanner sc = new Scanner(System.in);
    public static void main(String[] args) throws Exception {
        int n = sc.nextInt();
        int k = sc.nextInt();
        int[] ary = new int[n];
        for (int i = 0;i < n;i++) {
            ary[i] = sc.nextInt();
        }
        Arrays.sort(ary);
        System.out.println(ary[n-1]-ary[0]);
    }
}