import java.util.Scanner;

class main{
    public static void main(String args[]){
	Scanner scan = new Scanner(System.in);

	int N = scan.nextInt();
	int K = scan.nextInt();

	int max = 0;
	int min = 1000;

	for(int i = 0; i < N; i++){
	    int num = scan.nextInt();

	    max = Math.max(max, num);
	    min = Math.min(min, num);
	    
	}

	System.out.printf("%d\n", max - min);

    }
}