C++ Devre Hesabı Yapan Program

#include <iostream>
using namespace std;
double ToplamDirenc(double R1,double R2,double R3)
{ double Res;
 Res = 1 / (1/R1 + 1/R2 + 1/R3);
 return Res;
}
double AkimHesapla (double Res, double Volt)
{ double Sonuc;
 Sonuc = Volt / Res;
 return Sonuc;
}
double GucHesapla (double Akim, double Volt)
{ double Sonuc;
 Sonuc = Volt * Akim;
 return Sonuc;
}