#include <stdio.h>

int main()
{
	int x, n, distant;
	scanf("%d %d", &x, &n);

	int a = (x - 1 + n) / 7;
    int b = (x - 1 + n) % 7;
	if (b != 6 && b != 7)
		distant = (n - a * 2) * 250;
	else if (b == 6)
		distant = (n - a * 2 - 1) * 250;
	else if (b == 7)
		distant = (n - a * 2 - 2) * 250;

	printf("%d\n", distant);

	return 0;
}