abstract class link problem

[mehmedean]

hi all,

I'm doing a project and a encountered a very annoying problem. I want to define an abstract "composite3d" class and derive other classes such as "table", "chair", etc.. However, when I want to build after a successful compilation, I get the following error:

------------------------
Text1.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall Composite3D::draw(void)" (?draw@Composite3D@@UAEXXZ)
Debug/Text1.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.
------------------------

The code is below:

==================================
class Primitive3D
{
public:
int x,y,z;
bool isSelected;
};

class Composite3D
{
public:
Primitive3D *primitiveList;
int listSize;

virtual void draw();
};

class Table : public Composite3D
{
public:
Table();
void draw();
};

Table::Table ()
{
}

void Table::draw ()
{
}

void main ()
{
}
==================================

so is there anyone that knows what this basic problem is?

[firedraco]

You need to add an = 0; on the end to tell the compiler you aren't actually going to define it.

Also, use: int main().

[mehmedean]

thanks. in fact i know this and i suppose i tried it but i didn't obviously...