/*

* File: main.cpp

* Author: ngupta94

*

* Created on January 21, 2014, 11:53 AM

*/

#include <cstdlib>

#include <iostream>

using namespace std;

struct node //one element of stack

{

int data; //data item

node* next; //pointer to next link

};

class stack //a list of links

{

private:

node* head; //pointer to first link

public:

stack() //no-argument constructor

{

head = NULL;

} //no first link

void push(int d); //add data item (one link)

void display(); //display all link

int pop();

};

void stack::push(int d) //add data item

{

node *newNode = new node;

newNode->data = d;

newNode->next = head;

head = newNode;

return;

}

int stack::pop() {

node *tmp;

int d;

if (head == NULL) {

cout << "Stack Empty " << endl;

return(-1);

}

else {

tmp = head;

d = head->data;

head = head->next;

delete tmp;

}

return(d);

}

void stack::display() //display all links

{

node* current = head; //set ptr to first link

while (current != NULL) //quit on last link

{

cout << current->data << endl; //print data

current = current->next; //move to next link

}

}

/*

*

*/

int main(int argc, char** argv) {

stack q;

int ret;

ret = q.pop();

if (ret >=0 ) {

cout << "stack out = " << ret << endl;

}

q.push(56);

q.push(23);

q.push(87);

ret = q.pop();

if (ret >=0 ) {

cout << "stack out = " << ret << endl;

}

ret = q.pop();

if (ret >=0 ) {

cout << "stack out = " << ret << endl;

}

q.display();

return 0;

}