#include<iostream>

int main(void)
{
	int N, K, min, max, number, tmp;

	scanf("%d", &N);
	scanf("%d", &K);

	scanf("%d", &min);
	scanf("%d", &max);

	if(min > max)
	{
		tmp = min;
		min = max;
		max = tmp;
	}

	for(int i = 2; i < N; i++)
	{
		scanf("%d", &number);

		if(number < min)
			min = number;
		else if(number > max)
			max = number;
	}

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

	return 0;
}