difficulties with functions

[marhit]

I can't figure out the error. :/

#include <iostream>
#include <iomanip>
using namespace std;

// function prototypes
double getSales(double);
double calcComm(double);
void dispComm(double);
void calcTotal(double);
double dispTotal(double);

int main()
{
	double sales= 0.0;
	double total= 0.0;

	getSales(sales);
	calcComm(sales);
	dispComm(sales);
	calcTotal(sales);
	dispTotal(sales);

	system("pause");
	return 0;

}

double getSales(double sales)
{
	cout << "Enter sales amount: ";
	cin >> sales;
	return sales;
}

double calcComm(double sales)
{
	double comm= (sales * .10);
	return comm;
}

void dispComm(double comm)
{
	cout << "Commission: $";
}

double calcTotal(double comm, double sales)
{
	double total= (comm+sales);
	return total;
}

void displayTotal(double total)
{
	cout << "Total: $";
}

[Moschops]

Your functions calculate things and return those values they have calculated. You are ignoring the returned values.

Here is how to actually get the returned value.

double theReturnedValue = getSales(sales); or
comm = calcComm (sales);, for example.


You need to learn: functions ( http://www.cplusplus.com/doc/tutorial/functions/ )

[pogrady]

You intend to pass by reference but do not specify this in the function declaration.

read this:
http://www.cplusplus.com/doc/tutorial/functions2/