#include <iostream>

using namespace std;


class linkedListclass {
  friend class realList;
public:

  linkedListclass(int newvalue) {
    dvalue=newvalue;
    next = NULL;
  }

  void printlist() {
    cout << "current node is " << dvalue << endl;
    if (next != NULL)
      next->printlist();
    else
      cout << "\n\n";
  }

private:
  int dvalue;
  linkedListclass *next;

};

class realList {
public:
  realList(int nodevalue) {
    first = new linkedListclass(nodevalue);
    last = first;
  }

  ~realList() {
    linkedListclass *temp;
    cout << "called the destructor for realList \n";

    while (first != NULL) {
      temp = first;
      first = first -> next;
      cout << "deleting " << temp->dvalue << endl;
      delete temp;
    }
  }

  void addAtFront(int newvalue) {
    linkedListclass *newnode = new linkedListclass(newvalue);

    newnode->next = first;
    first = newnode;
  }

  int delFromFront() {
    int retval;
    linkedListclass *temp;

    retval =  first->dvalue;
    temp = first;
    if (first == last) {
      first = last = NULL;
    }
    else
      first = first-> next;

    delete temp;
    return retval;
  }

  int getdvalue() {
    return(first->dvalue);
  }

  void printlist() {
    first->printlist();
  }


private:

  linkedListclass *first, *last;
};

class mystack {
public:

  mystack () {
    stacklist = NULL;
  }

  void push (int newvalue) {
    if (stacklist == NULL)
      stacklist = new realList(newvalue);
    else
      stacklist->addAtFront(newvalue);
  }

  int pop () {
    return stacklist->delFromFront();
  }


private:

  realList *stacklist;
};

int main() {

  mystack *myList;

  myList= new mystack;

  myList->push(23);

  myList->push(45);

  myList->push(10);

  int delval = myList->pop();
  cout << "just deleted " << delval << endl;

  delval = myList->pop();
  cout << "just deleted " << delval << endl;

  delval = myList->pop();
  cout << "just deleted " << delval << endl;

  delete myList;

  return 0;
}