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

public class Main {
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        
        int N = sc.nextInt();
        int K = sc.nextInt();
        
        int[] num = new int[N];
        for(int i = 0; i < N; i++) 
            num[i] = sc.nextInt();
        
        Arrays.sort(num);
        System.out.println(num[N] - num[0]);
    }
}