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

public class Main{

	static final Scanner	s	=new Scanner(System.in);

	public static void main(String args[]){
		input();
		solve();
	}


	static int n,k,a[];
	private static void input(){
		n=s.nextInt();
		k=s.nextInt();
		a=new int[n];
		for(int i=0;i<n;i++) {
			a[i]=s.nextInt();
		}
		Arrays.sort(a);
	}

	private static void solve(){
		System.out.println(a[a.length-1]-a[0]);
	}
}