// a simple client to drive the stack
// one improvement may be to have the client maintain a free list of unused nodes
int main()
{
STACK s;
STACK_NODE *p;
bool done = false;
int option, value;
while( !done )
{
cout << "1) push\n2) pop\n3) peek\n4) pop all\n5) init\n"
<< "6) check if empty\n7) quit\n\nEnter option : " << flush;
cin >> option;
switch( option )
{
case 1: cout << "Enter value to push : " << flush;
cin >> value;
p = new STACK_NODE;
p->key = value;
s.push( p );
break;
case 2: if( !s.IsEmpty() )
{
p = s.pop();
value = p->key;
delete p;
cout << "Popped " << value << endl;
}
else
{
cout << "Nothing to pop!" << endl;
}
break;
case 3: if( !s.IsEmpty() )
{
// cast off const-ness (but DON't mess with the data!)
p = const_cast<STACK_NODE *>(s.peek());
value = p->key;
cout << "Peeked " << value << endl;
}
else
{
cout << "Nothing to peek!" << endl;
}
break;
case 4: while( !s.IsEmpty() )
{
p = s.pop();
value = p->key;
delete p;
cout << "Popped " << value << endl;
}
cout << "Stack is now empty" << endl;
break;
case 5: cout << "Initializing..." << endl;
s.init();
break;
case 6: cout << "IsEmpty returns " << ( s.IsEmpty() ? "true" : "false" ) << endl;
break;
case 7: done = true;
break;
default: cout << "What?" << endl;
}
}
return 0;
}
