#include <iostream>
using namespace std;
int main()
{
	int x,n;
	cin >>x>>n;
	int d=n/7*5; 
	int r=n%7;
	if (r>0) 
	{
		if (r+x== 7and x==7) 
			r-=1;
		else if (r+x>=8) 
			r-=2;
	}
	cout << (d+r)*250;
	return 0;
}