#include<iostream>
#include<cstdio>
using namespace std;
int main()
{
    int a1, b1, a2, b2;
    double c1, c2;
    cin >> a1 >> b1 >> c1;
    cin >> a2 >> b2 >> c2;
    printf("VALOR A PAGAR: R$ %.2lf" ,b1 * c1 + b2 * c2);

    return 0;
}