import java.io.*;
import java.util.*;
import java.math.*;

class Main21 {
	
	public static void main (String[] args) throws IOException {
		BufferedReader br = 
			new BufferedReader(new InputStreamReader(System.in));
		
		int n = Integer.parseInt(br.readLine());
		int k = Integer.parseInt(br.readLine());
		int[] nums = new int[n];
		int max = 0, min = 1001;
		for (int i = 0; i < n; i++) {
			nums[i] = Integer.parseInt(br.readLine());
			max = Math.max(max, nums[i]);
			min = Math.min(min, nums[i]);
		}
		
		System.out.println(max - min);
	}
}