#include<bits/stdc++.h>
using namespace std;
int main(){
	long long int x,n;
	cin>>x>>n;
	if(n>=7){
		cout<<(n-(n/7*2))*250<<endl;
	}else{
		if(x+n<7){
			cout<<n*250<<endl;
		}else{
			cout<<(n-2)*250<<endl;
		}
	}
	return 0;
}