#ifndef mySTACKS_H #define mySTACKS_H #include "mySTACK.h" namespace mySTACKS { class ListStack: public STACK { struct Node { int data; Node* next; Node(int data, Node* next); }; Node* head; ListStack(); public: friend STACK* STACK::getInstance(int); int pop(); void push(int data); bool empty(); ~ListStack(); }; class ArrayStack : public STACK { int top; int* arr; ArrayStack(); public: friend STACK* STACK::getInstance(int); void push(int data); int pop(); bool empty(); ~ArrayStack(); }; } #endif