Compute the number of molecules

I would like my program to be reviewed. I had to write a simple program that calculates the number of molecules in a hydrocarbon.

• 1 carbon atom has 12 AMU.

• 1 hydrogen atom has 1 AMU.

#include 
using namespace std;

int main()
{
    cout > mass >> carbonAtoms >> hydrogenAtoms;

    long formulaWght = (carbonAtoms * 12) + (hydrogenAtoms * 1);

    double molecules = (mass / formulaWght) * 6.02e23;

    cout << mass << " grams of hydrocarbon\nwith "
            << carbonAtoms << " carbon atom(s) and "
               << hydrogenAtoms << " hydrogen atom(s)\ncontains "
                  << molecules << " molecules" << endl;

    return 0;
}

• Do not use using namespace std. Read

this

-
Instead of using "magic numbers" in your program. Use symbolic
constants. CARBON_AMU and HYDROGEN_AMU should be ints.

const int CARBON_AMU= 12;
const int HYDROGEN_AMU = 1;
const double AVOGADRO = 6.02214141070409084099072e23;

-
Utilize functions in your program, instead of initializing a
variable with an expression:

long formulaWeight(int carbonAtoms, int hydrogenAtoms){
    return((carbonAtoms * CARBON_AMU) + (hydrogenAtoms * HYDROGEN_AMU));
}

double numMolecules(float mass, long formulaWeight)
{
    return((mass / formulaWeight) * AVOGADRO);
}

-
`(e.g. 10.5 2 6): "

-
Fix your indentation. This is much easier to read:

cout << mass << " grams of hydrocarbon\nwith "
     << carbonAtoms << " carbon atom(s) and "
     << hydrogenAtoms << " hydrogen atom(s)\ncontains "
     << molecules << " molecules" << endl;

StackExchange Code Review Q#65332, answer score: 4