#include<stdio.h>
int main()
{
	int x, n,count=0;
	int sum = 0;
	scanf_s("%d %d", &x, &n);
	
	if (x > 5)
	{
		
		count = n / 7;
		sum = (n - (8 - x) - (2*count)) * 250;
	}
	else
	{
		count = n /7;
		sum = (n - (2*count)) * 250;
	}
	printf("%d", sum);
	return 0;
}