linker error caused by class - help needed

[turlisk]

i'm working on a small project and i created a class called item that takes two arguments one double and one int,

i've i have a default blank build for that class with no arguments as well where the user can set them if needed.

i'm trying to make an array of them and i'm getting a linker error for unresolved externals

here is a segment of my code.

[code]
class Item
{
public:
// Constructors
Item();
Item(double price, int gramsOfFat);
private:
double price;
int gramsOfFat;
}

void main ()
{
const int MAX_ITEMS = 10;
Item vendingMachine[MAX_ITEMS];
// other stuff
double Price = 0;
int GramsOfFat = 0;
}

I have other code but i think this is the problem, any help would be great.

[Nikitozz]

First of all, it would be helpful to see the exact error message.
Second, you implemented both of your constructors, didn't you?

[turlisk]

main.obj : error LNK2019: unresolved external symbol "public: __thiscall Item::Item(void)" (??0Item@@QAE@XZ) referenced in function _main

F:\VendingMachineQuizStudent\Debug\VendingMachineQuiz.exe : fatal error LNK1120: 1 unresolved externals

here is a little more of my code

class Item
{
public:
	// Constructors
	Item();
	Item(double price, int gramsOfFat);

	// Methods
	void setPrice(double pPrice)
	{
		price = pPrice;
	}
	void setGramsOfFat(int pGramsOfFat)
	{
		gramsOfFat= pGramsOfFat;
	}
	double getPrice()
	{
		return price;
	}
	int getGramsOfFat()
	{
		return gramsOfFat;
	}
	double raisePrice(double raisedPrice)
	{
		price += raisedPrice;
	}

private:
	double price;
	int gramsOfFat;
	double raisedPrice;
};


void main()
{
        //constants and classes
        const int MAX_ITEMS = 10;
	Item vendingMachine[MAX_ITEMS];
        // other variables
	double Price = 0;
	int GramsOfFat = 0;
	string textSpacer = "     ";
	string vendStrPrice = "Price";
	string vendStrFatGrams = "Fat Grams";

	srand( (unsigned)time( NULL ) );

	for (int i = 0; i <= MAX_ITEMS; i++)
	{
		vendingMachine[i].setPrice((rand()%175 + 75) / 100);
		vendingMachine[i].setGramsOfFat(rand()%30 + 5);
	}
	cout.setf(ios::showpoint);
	cout.precision(2);
	cout << left << vendStrPrice << textSpacer << vendStrFatGrams << endl;
	for (int i = 0; i <= MAX_ITEMS; i++)
	{
		cout << left << cout << vendingMachine[i].getPrice() << textSpacer 
		<< vendingMachine[i].getGramsOfFat() << endl;
	}

[Skizmo]

	Item();
	Item(double price, int gramsOfFat);

These 2 functions are only declared, not implemented.

[turlisk]

	Item();
	Item(double price, int gramsOfFat);

These 2 functions are only declared, not implemented.

down in my main function i have declared my item class as an array, is there a different way to declare this?

[OneEyeMan]

Hi,
You need to do this:

Item::Item()
{
}

Item::Item(double price, int gramsOfFat)
{
        m_price = price;
        m_gramsOfFat = gramsOfFat;
}

or put this in the class definition.

and then in your class definition you need this:

class Item
{
...........
private:
     double m_price;
     int m_gramsOfFat;
};

Notice the "m_" prefix here.

HTH.

Thank you.

[Skizmo]

down in my main function i have declared my item class as an array, is there a different way to declare this?

What you are doing in the main function has nothing to do with this. You declared 2 constructors, but never implemented the functions itself.

[turlisk]

What you are doing in the main function has nothing to do with this. You declared 2 constructors, but never implemented the functions itself.

cool got it thanks guys,

instead of starting a new topic i'm going to append it to this one if that is okay..

I think i have a logic math error.

i'm trying get a value between 0.75 and 1.75 randomly set i keep getting 2 and 3's and not sure why.

i've set up the line of code as follows

	for (int i = 0; i < MAX_ITEMS; i++)
	{
		vendingMachine[i].setPrice((rand()%175 + 75.0 / 100.0));
		vendingMachine[i].setGramsOfFat(rand()%30 + 5);
	}

now if i'm doing this right if the cap is 175 on the random number then i'm adding 75 to it incase it is 0.

i keep getting odd results even numbers like 1.3e+002

i have placed in a 2 point precision and later cout the results i think i may be messing something up or overlooked something.

[Paul McKenzie]

cool got it thanks guys,

instead of starting a new topic i'm going to append it to this one if that is okay..

I think i have a logic math error.

i'm trying get a value between 0.75 and 1.75 randomly set i keep getting 2 and 3's and not sure why.

1) Generate a random number between 0 and 100.

2) add 75 to 1).

3) divide 2) by 100.

Regards,

Paul McKenzie

[turlisk]

thanks guys got it all figured out now.