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class problems

gunsman (3)
I am getting multiple errors,the first is in int main under switch case 4, it says meter must have a point to function and i have no idea what that means or what i have to do for that. second issue is void tracker::input ( ), it is saying tracker::input can't be re declared outside of its class, but when i ran this program without the switch statements this error wasn't occurring.
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#include <iostream>
using namespace std;

class tracker
{
public:
	void input ( );
	void efficiency ( );
	void set (int newtrips, double newmiles, double newgas);
	void set (double miles, double gas);
	void set (int changemiles);
	double getgas( );
	double getmiles( );
	double efficiency;
private:
	int trips;
	double miles, gas;
};
int main ()
{
	int x;
	tracker meter;
	meter.input ( );
	cout << "What would you like to do?" << endl;
	cout << "1. Enter a new set of trips, mileage and gas usage" << endl;
	cout << "2. Output fuel used" << endl;
	cout << "3. Output mileage" << endl;
	cout << "4. Output fuel efficiency" << endl;
	cout << "5. Exit" << endl;
	cout << "Your choice: ";
	cin >> x;
	switch (x)
	{
	case 1:
		meter.input ( );
	case 2:
		meter.getgas( );
	case 3:
		meter.getmiles( );
	case 4:
		meter.efficiency ( );
}
void tracker::input ( )
{
	cout << "How many trips do you wish to make? ";
	cin >> trips;
	cout << "How many miles in total ae you driving? ";
	cin >> miles;
	cout << "How many gallons of gas are used? ";
	cin >> gas;
}
void tracker::efficiency ( )
{
efficiency = miles/gas;
return efficiency;
}
void tracker::set(int newtrips, double newmiles, double newgas)
{
	cout << "How many trips do you wish to make? ";
	cin >> trips;
	cout << "How many miles in total ae you driving? ";
	cin >> miles;
	cout << "How many gallons of gas are used? ";
	cin >> gas;
}
double tracker::getgas( )
{
	return gas;
}
double tracker::getmiles( )
{
	return miles;
}
Chervil (7320)
Several issues.
One, there is no closing brace for switch (x) { in function main().

In class tracker, the name "efficiency" is declared twice, first as the name of a member function, then as the name of a variable.

In the definition of that function, there are related problems.

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void tracker::efficiency ( )
{
efficiency = miles/gas;
return efficiency;
}


First, that same doubly-defined name is referenced again. Second, a void function does not return a value.

You could try something like this:
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void tracker::efficiency ( )
{
    eff = miles/gas;
}


Here, eff is simply a renamed version of the original variable. The member variable of the class will need to be renamed to match.


gunsman (3)
thank you for the help, silly me forgot to put the close bracket but now another issue. I have to use an accessor function to print out total miles and total gas, here is what i have under a switch case
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meter.getgas( );
		system ("pause");
		break;


and the accessor to go with it
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double tracker::getgas( )
{
	return gas;
}


my problem is i can't get it to print out without moving gas to public instead of remaining private where the prof wants it
Chervil (7320)
Do you mean you tried this but it didn't work:
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    cout << meter.getgas( );
    system ("pause");
    break;

(there was no cout in the code you posted).
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