import java.util.Scanner;
	

public class Main{
	
	
	public static void main(String args[])throws Exception{
		
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int K = sc.nextInt();
		int max = 0;
		int min = 1001;
		for(int i=0;i<N;i++){
			int n = sc.nextInt();
			max = Math.max(max, n);
			min = Math.min(min, n);
		}
		System.out.println(max-min);
	}
	
}