#include <iostream>
using namespace std;

int main()
{
	int x,n,n1,n2,t,t1,t2;cin >> x >> n;
	n1 = n / 7;//周期数
	n2 = n % 7;//周期之外
	if (x = 1)
	{
		if (n2 >= 5)t2 = 1250;
		else t2 = (n2+1) * 250;
	}
	if (x = 2)
	{
		if (n2 < 4)t2 = (n2+1) * 250;
		else if (n2 > 5)t2 = (n2 - 1)*250;
        else t2 = 1000;	
	}
	if (x = 3)
	{
		if (n2 < 3)t2 = (n2+1) * 250;
		else if (n2 > 4)t2 = (n2 - 1)*250;
        else t2 = 750;
	}
	if (x = 4)
	{
		if (n2 < 2)t2 = (n2+1) * 250;
		else if (n2 > 3)t2 = (n2 - 1)*250;
        else t2 = 500;	
	}
	if (x = 5)
	{
		if (n2 < 1)t2 = (n2+1) * 250;
		else if (n2 > 2)t2 = (n2 - 1)*250;
        else t2 = 250;	
	}
	if (x = 6)
	{
		if (n2 <= 1)t2 = 0;
		else t2 = (n2 - 2)*250;
	}
	if (x =7)
	{
		if (n2 < 6)t2 = n2 * 250;
		else t2 = 1250;
	}
	t1 = n1 * 1250;
	t = t1 + t2;
	cout << t;
		
	return 0;
}