#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
int x1, x2, y1, y2;
double x3, y3, P;
scanf("%d%d%lf\n",&x1,&x2,&x3);
scanf("%d%d%lf\n",&y1,&y2,&y3);
printf("VALOR A PAGAR: R$ %.2lf",x2 * x3 + y2 * y3);
return 0;
}