import java.util.Scanner;
class N021{
	public static void main(String args[]){
		Scanner s = new Scanner(System.in);
		int n = s.nextInt();
		int k = s.nextInt();
		int max = 0;
		int min = 1000;
		int a[] = new int[n];
		for(int i = 0; i < n; i++){
			a[i] = s.nextInt();
			max = Math.max(max, a[i]);
			min = Math.min(min, a[i]);
		}
		System.out.println(max - min);
	}
}