#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
	int x;
	int n;
	int answer=0;
	cin >> x >> n;
	
	for (int i=1; i<=n/7; i++)
	{
		for (int j=1; j<=7; j++)
		{	
			if (j!=6 || j!=7)
			{
				answer+=250;
			}
		}
	}
	
	int sum=n%x*250+answer;
	cout << answer;
}