Thread: What am i doin wrong?!

when i run this code.. the output is all wrong.. can u help me out?
the formatting looks all weird here.. but when cut and pasting it back to vc++ makes it readable...

#include <iostream.h>
#include <string.h>

// Node class definition:
template <class Item>
class Node // Node for use with the Stack class defined below.
{ // Data items stored in a node must have a copy
public: // constructor.
Node();
Node(const Item& data);
~Node();

void setData(const Item& data); // Mutators
void setNext(Node* next);

Item getData() const; // Accessors
Node* getNext() const;

private:
Node* _next; // Pointer to the next node.
Item* _data; // Pointer to the data contained in the node.
};

// Default Node constructor:
template <class Item>
Node<Item>::Node()
{
_next = NULL; // Default is an empty node with no next node.
_data = NULL;
}

// One parameter Node constructor:
template <class Item>
Node<Item>::Node(const Item& data)
{
_data = new Item(data); // Makes copy of the input data.
_next = NULL; // No next node by default.
}

// Node destructor:
template <class Item>
Node<Item>::~Node()
{
if (_data != NULL) delete _data; // Give back the memory for data storage.
}

// Node mutators:
template <class Item>
void Node<Item>::setData(const Item& data)
{
if (_data != NULL) delete _data; // Prevent memory leaks.
_data = new Item(data); // Makes a copy of the input data.
}

template <class Item>
void Node<Item>::setNext(Node* next)
{
_next = next;
}

// Node accessors:
template <class Item>
Item Node<Item>::getData() const
{
return *_data;
}

template <class Item>
Node<Item>* Node<Item>::getNext() const
{
return _next;
}

// Stack class definition:
template <class Item> // A versatile stack ADT.
class Stack
{
public:
Stack(); // Default constructor.
~Stack(); // Destructor (doesn't need a copy constructor).

void push(const Item& entry); // Mutators
Item pop();

int empty(); // Accessors
Item peek();

private:
Node<Item>* _top; // Data are stored in a sequence of linked nodes.
};

// Stack default constructor:
template <class Item>
Stack<Item>::Stack()
{
_top = NULL; // Empty stack by default.
}

// Stack destructor:
template <class Item>
Stack<Item>::~Stack()
{
Item temp;

while (_top != NULL)
{
temp = pop();
}
}

// Stack push() implementation:
template <class Item>
void Stack<Item>:ush(const Item& entry)
{
Node<Item>* temp;
temp = new Node<Item>(entry);
temp->setNext(_top);
_top = temp;
}

// Stack pop() implementation:
template <class Item>
Item Stack<Item>:op()
{
Item temp = NULL;
Node<Item>* next;

if (_top != NULL)
{
temp = _top->getData();
next = _top->getNext();
delete _top;
_top = next;
}
else
{
cout << "Attempt to pop an empty stack!";
}
return temp;
}

void main()
{
Stack <int> intStack;
int popInteger, i;
cout << "processing an integer Stack"<< endl;

for (i = 0; i < 4; i++){
intStack.push(i);
}

for (i = 4; i>0 ; i--){
intStack.pop();
cout<<popInteger<<" popped from Stack"<<endl;
}
}

thank you, so i removed the popInterger variable al ogether as suggeted.. and it works out find.. what i can't figure is upon popping the integers.. there is only 2 int to pop...

when i increase the int i to see the problem, the intergers to pop are always 1/2 the intergers i pushed in.

how do i solve that?

Rolando

well now i wanna push and pop characters from a character array..
this is what i tried but it is not working:

void main()
{
Stack <int> intStack;
int i;
char str[10];
cin>>str;

for (i = 0; str[i] < 10; i++){
intStack.push(str[i]);
}

for (i = 0; str[i]<10 ;i++){
cout<<intStack.pop()<<" popped from Stack"<<endl;
}
}


what's wrong here?

thanks