import java.util.*;

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