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ArrayList.h

#pragma once

template

class ArrayList

{

private:

// attributes

const static int DEFAULT_SIZE = 5; // constant for the initial size

T* list; // pointer to the array

int count; // number of items in the list

int capacity; // current size in memory

public:

// constructors

ArrayList(void)

{

this->list = new T[DEFAULT_SIZE];

this->capacity = DEFAULT_SIZE;

this->count = 0;

}

ArrayList(int initialCapacity)

{

this->list = new T[initialCapacity];

this->capacity = initialCapacity;

this->count = 0;

}

// destructor

~ArrayList(void)

{

// delete the array pointer

if (this->list != nullptr)

{

delete[] this->list;

this->list = nullptr;

}

}

/// Determine if the ArrayList is empty

bool isEmpty(void)

{

return count == 0; // array is empty if it has zero items

}

/// Get the item at the given position

T get(int position)

{

if (position < count)

return list[position];

else

return NULL;

}

/// Add an item to the ArrayList

void add(T data)

{

// if the array is full, double the size

if (count == capacity)

{

// bigger array

capacity = 2 * capacity;

T* temp = new T[capacity];

// copy items from current array to bigger array

for (int i = 0; i < count; i++)

{

temp[i] = list[i];

}

// delete the current array

delete[] list;

// rename the bigger array to the current array name

list = temp;

}

// add the data item to the array

list[count] = data;

// increment the count

count++;

}

/// Remove item at the given position

void removeAt(int position)

{

// replace every item from that position on with the next item

for (int i = position; i < count - 1; i++) // notice "count - 1" to copy last item to next to last position

{

list[i] = list[i + 1];

}

// decrease the item count

count--;

}

/// Get the count of items in the ArrayList

int getCount(void)

{

return count;

}

/// Get the ArrayList current capacity

int getCapacity()

{

return capacity;

}

};

Source.cpp

#include

#include

#include

#include "ArrayList.h"

using namespace std;

/// Entry point to the application

int main(void)

{

// check for memory leaks

#if defined(DEBUG) | defined(_DEBUG)

_CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF);

#endif

// an int ArrayList

ArrayList intList;

intList.add(27);

intList.add(13);

intList.add(42);

intList.add(31);

intList.add(22);

intList.add(19);

for (int i = 0; i < intList.getCount(); i++)

{

cout << intList.get(i) << ", ";

}

cout << " " << endl;

cout << "Count: " << intList.getCount() << endl;

cout << "Capacity: " << intList.getCapacity() << endl;

cout << " " << endl;

// a string ArrayList

ArrayList strList;

strList.add("Brendan");

strList.add("Maria");

strList.add("Ivan");

strList.add("Nathan");

// display list data

for (int i = 0; i < strList.getCount(); i++)

{

cout << strList.get(i) << ", ";

}

cout << " " << endl;

cout << "Count: " << strList.getCount() << endl;

cout << "Capacity: " << strList.getCapacity() << endl;

// pause

cout << " Press any key to continue...";

cin.sync();

_getch();

return 0;

}