#include<stdio.h>

int main(void)
{
	int n, k;
	int ni[9];
	int max = 0;
	int min = 1000;
	int i;

	scanf("%d", &n);
	scanf("%d", &k);

	for (i = 0; i < n; i++)
		scanf("%d", &ni[i]);

	for (i = 0; i < n; i++) {
		if (max < ni[i])
			max = ni[i];
		if (min > ni[i])
			min = ni[i];
	}
	printf("%d\n", max - min);

	return 0;
}