#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<math.h>
#include<string.h>
#define ll long long
int main()
{
	ll x, n,l=0;
	scanf("%lld%lld", &x, &n);
	if (x == 6)
	{
		n-=2;
	}
	if (x == 7)
	{
		n--;
	}
	if (n <= 0)
		printf("0\n");
	else
	{
		if(x!=6&&x!=7)
		{
			l = 250 * (6 - x);
			n -= 2 + (6 - x);
		}
		if (n <= 0)
			printf("%lld\n",l);
		else
		{
			l += 250 * 5 * (n / 7) + 250 * (n % 7);
			printf("%lld\n", l);
		}
	}
	return 0;
}