#include <iostream>

int main(void)
{
	int N, K;

	std::cin >> N >> K;
	
	int a[N];
	
	int min, max;
	
	for(int i = 0; i < N; i ++)
	{
		std::cin >> a[i];
		
		if(i == 0)
		{
			min = a[i];
			max = a[i];
		}
		if(i != 0)
		{
			if(a[i] > max)
			{
				max = a[i];
			}
			
			if(a[i] < min)
			{
				min = a[i];
			}
		}
	}
	
	std::cout << (max - min) << std::endl;

	return 0;
}