#include<bits/stdc++.h>
using namespace std;

int main()
{
	long long x , n , sum = 0;
	cin >> x >> n;
	while (n > 0)
	{
		if(x == 6)
		{
			x += 2;
			x -= 7;
			n -= 2;
		}
		if(x == 7)
		{
			x = 1;
			n -= 1;
		}
		n -= 1;
		x++; 
		sum += 250;
	}
	cout << sum << endl;
}