#include <iostream>
#include <iomanip>
using namespace std;
int main() {
    int x, n,a,b,c,t;
    cin >> x >> n;
    if (x > 5) {
        a = 7-x;
        b = (n-a) / 7, c = (n-a) % 7;
            if (c > 2)t = b * 5 + c - 2;
            else t = b * 5;
    }
     else {
        a = 6 - x;
        if (n < a) t = n;
        if (a + 2 > n && n > a)t = n;
        if (n >=(a + 2)) {
            b = (n - a) / 7, c = (n - a) % 7;
            if (c > 2)t = b * 5 + c - 2 + a;
            else t = b * 5 + a;
        }
    }
    cout << t*250;
    return 0;
}