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

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