#include <iostream>
#include <vector>

int main()
{
	int n;
	int64_t K;
	std::cin >> n >> K;
	std::vector<int64_t> xs(n);
	std::vector<int64_t> ys(n);
	for (int i = 0; i < n; i++)
	{
		std::cin >> xs[i] >> ys[i];
	}

	if (K == 0)
	{
		std::cout << "0" << std::endl;
		return 0;
	}

	int64_t bestdiamsq = 0;
	int count = 0;
	int j = 0;
	for (int i = 0; i < n; i++)
	{
		int ip1 = (i + 1) % n;
		int64_t dx = xs[ip1] - xs[i];
		int64_t dy = ys[ip1] - ys[i];
		while (true)
		{
			int64_t dx1 = xs[j] - xs[i];
			int64_t dy1 = ys[j] - ys[i];
			int64_t distsq = dx1 * dx1 + dy1 * dy1;
			int64_t area1 = dx * dy1 - dy * dx1;

			int nextj = (j + 1) % n;

			if (distsq > bestdiamsq)
			{
				bestdiamsq = distsq;
				count = 0;
			}

			if (nextj != i && j != ((i + 1) % n) && distsq == bestdiamsq)
			{
				count++;
			}

			int64_t dx2 = xs[nextj] - xs[i];
			int64_t dy2 = ys[nextj] - ys[i];
			int64_t area2 = dx * dy2 - dy * dx2;
			if (area2 < area1)
				break;
			else
				j = nextj;
		}
	}

	count /= 2;

	int64_t low = 0;
	int64_t high = 1;

	while (4LL * high * high * bestdiamsq < K * K)
		high *= 2LL;
	while (high - low > 1LL)
	{
		int64_t mid = low + (high - low) / 2LL;
		if (4LL * mid * mid * bestdiamsq < K * K)
			low = mid;
		else
			high = mid;
	}

	//  std::cout << high << " " << count << std::endl;

	if (4LL * high * high * bestdiamsq == K * K && high > count)
		high++;

	std::cout << high << std::endl;
}