stack.h

Code

/*
    stack.h
    CIS 250
    Dave Klick
    
    Definition and implementation of a stack class for integer
    values which uses an array for storage.
    This class should really overload the assignment operator
    and copy constructor, but doesn't at the moment.
*/

#ifndef __STACK_H_
#define __STACK_H_
#include <cstdlib>

class stack {
private:
    int* stk;
    int numItems;
    int size;
    void init(const int size);
public:
    stack();
    stack(const int size);
    ~stack();
    bool isEmpty() const;
    bool isFull() const;
    bool push(const int data);
    bool pop(int& data);
};

stack::stack() { init(10); }

stack::stack(int size) { init(size); }

void stack::init(const int len) {
    size = len>0 ? len : 10;
    stk = new int[size];
    numItems = 0;
}

stack::~stack() {
    if (stk) delete[] stk;
    stk = NULL;
    numItems = 0;
    size = 0;
}

bool stack::isEmpty() const { return numItems==0; }

bool stack::isFull() const { return numItems==size; }

bool stack::push(const int data) {
    if (isFull()) return false;
    stk[numItems++] = data;
    return true;   
}

bool stack::pop(int& data) {
    if (isEmpty()) return false;
    data = stk[--numItems];
    return true;
}

#endif