#include <stdio.h>
int main()
{
	int x,n=0;
	scanf("%d %d",&x,&n);
	int a=0;
	int work=0;
	if(x==6){
		a=n-2;
		work=(a/7)*5+(a%7);
	}
	if(x==7){
		a=n-1;
		work=(a/7)*5+(a%7);
	}
	if(x<6){
		a=n-(8-x);
		work=(a/7)*5+(a%7)+(6-x);
	}
	int km=0;
	km=work*250;
	printf("%d",km);
	return 0;
}