Compile time error

[shrew83]

Hi, could anyone please tell me what is the problem with the following code :

const int MAX = 100;

class Stack{
protected:
int stk[MAX];
int top;
public:
Stack()
{ top = 0; }
void push(int var)
{ cout<<"Top = "<<top<<endl;
stk[++top] = var;
cout<<"Top after = "<<top<<endl;
}
int pop()
{ cout<<"Top POP = "<<top<<endl;
return stk[top--]; }
};
class Stack2: public Stack
{
public:
void push(int var)
{
//Stack s;
if (top != MAX){
cout<<"Stack2 push"<<endl;
void Stack::push(int var);
}
else
cout<<"Stack is full"<<endl;
}
int pop()
{
if ( top > 1)
return Stack::pop();
else
cout<<"Nothing to pop"<<endl;
}
};

int main(int argc, char *argv[])
{
Stack2 s1;
cout<<"In the Program"<<endl;
s1.push(11);
s1.push(22);
s1.push(33);

cout<<"S 1 = "<<s1.pop()<<endl;
cout<<"S 2 = "<<s1.pop()<<endl;
cout<<"S 3 = "<<s1.pop()<<endl;
cout<<"S 4 = "<<s1.pop()<<endl;

getchar();
return 0;
}

The error is :
cannot declare member function 'Stack::push' within Stack2

Thanks

[weaknessforcats]

quote=shrew83]
class Stack2: public Stack
{
public:
void push(int var)
{
//Stack s;
if (top != MAX){
cout<<"Stack2 push"<<endl;
void Stack::push(int var); <<<<<<<<<<<<<<<<<<<<<<<
}
etc...
[/code]

The <<<<<<< line is a function prototype. It redefines the one in the Stack class. Redefinitions are not allowed in C++.

[shrew83]

Ok then how do I implement the scenario wherein I want to call the the push function of Stack from the push function of Stack2.

[weaknessforcats]

Stack2 inherits from Stack. That means it inherits the push function. Just call push() using your Stack2 object and the call will be made to Stack::push().

Remember, a derived object, like a Stack2 object, has an embedded base object (Stack) inside. In reality, the Stack2 call to the Stack::push() will push the data that's inside the base portioin of the Stack2 object.

There is no need for a push method in Stack2.