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

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