ListClass

#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;

typedef int ElementType;
const ElementType CAPACITY = 20;
const ElementType DEFAULT_VALUE = 0;

class List
{
private:

	ElementType dataList[CAPACITY]; //array to hold data
	int currentpos; //hold value of the currently active position
	int numOfElements; //number of elements within the array

	void createDataListArray()
	{
		for (currentpos; currentpos < CAPACITY; currentpos++)
			dataList[currentpos] = DEFAULT_VALUE;
	}

	friend ostream& operator<<(ostream& os, const List& lst)
	{
		for (int i = 0; i < CAPACITY; i++)
		{
			os << lst.dataList[i] << " ";
		}
		return os;
	}

public:
	//Constructor
	List()
	{
		first();
		numOfElements = 0;
		for (int i = 0; i < CAPACITY; i++)
		{
			dataList[i] = DEFAULT_VALUE;
		}
	}
	//Copy Constructor
	List(const List &obj)
	{
		first();
		numOfElements = obj.size();
		for (int i = 0; i < CAPACITY; i++)
		{
			dataList[i] = obj.dataList[i];
		}
	}

	bool empty() //go back and for loop entire array to check if empty
	{
		if (dataList[0] == 0)
			return true; //is empty
		else
			return false; //is not empty
	}

	void first()
	{
		currentpos = 0;
	}

	void last()
	{
		currentpos = numOfElements - 1;
	}

	void prev()
	{
		currentpos--;
	}

	void next()
	{
		if(currentpos < numOfElements - 1)
			currentpos++;
	}

	ElementType getPos()
	{
		return currentpos;
	}

	void setPos(int position)
	{
		currentpos = position;
	}

	void insertBefore(int value)
	{
		/*temp++;
		for (int i = CAPACITY-1; i >= currentpos; i--)
			dataList[i + 1] = dataList[i];
		dataList[currentpos] = value;
		numOfElements = temp; //numofElements kept resetting when loop starts*/
		for (int i = CAPACITY - 2; i >= currentpos; i--)
			dataList[i + 1] = dataList[i];
		dataList[currentpos] = value;
		numOfElements++; //numofElements kept resetting when loop starts
	}

	void insertAfter(int value)
	{
		/*temp++;
		for (int i = CAPACITY; i > currentpos; i--)
			dataList[i + 1] = dataList[i];
		dataList[currentpos + 1] = value;
		numOfElements = temp; //numofElements kept resetting when loop starts*/
		if (numOfElements == 0)//empty list
			dataList[0] = value;
		else
		{
			for (int i = CAPACITY - 2; i > currentpos; i--)
				dataList[i + 1] = dataList[i];
			dataList[currentpos + 1] = value;
			currentpos++;
		}
		numOfElements++; //numofElements kept resetting when loop starts

	}

	ElementType getElement()
	{
		return dataList[currentpos];
	}

	int size() const
	{
		return numOfElements;
	}

	void replace(ElementType value)
	{
		dataList[currentpos] = value;
	}

	void erase()
	{
		dataList[currentpos] = 0;
		numOfElements--;
	}

	void clear()
	{
		numOfElements = 0;
		createDataListArray();
	}

	void operator = (const List &right)
	{
		first();
		numOfElements = right.size();
		for (currentpos; currentpos < CAPACITY; currentpos++)
		{
			dataList[currentpos] = right.dataList[currentpos];
		}
	}

	bool operator == (const List &right)
	{
		bool status;

		for (int i = 0; i < CAPACITY; i++)
		{
			if (dataList[i] == right.dataList[i])
				status = true;
			else
				status = false;
		}
		return status;
	}

};

int main()
{
	List a, b;  int endit;

	for (int i = 1; i <= 20; i++)
		a.insertAfter(i * 2);
	cout << "List a : " << endl; //array should be filled [2,4,6,...]
	cout << "  " << a << endl;
	cout << "Number of elements in a - " << a.size() << endl;

	for (int i = 1; i <= 20; i++)
		b.insertBefore(i * 2);
	cout << "List b : " << endl;
	cout << "  " << b << endl;
	cout << "Number of elements in b - " << b.size() << endl;

	if (a == b)
		cout << "List a & b are equal" << endl;
	else
		cout << "List a & b are Not equal" << endl;

	a.first();
	b.first();
	cout << "First elmenet in list a & b: " << a.getElement() << ", "
		<< b.getElement() << endl;
	for (int i = 0; i < a.size(); a.next(), i++);
	for (int i = 0; i < b.size(); b.next(), i++);
	cout << "Last elmenet in list a & b: " << a.getElement() << ", "
		<< b.getElement() << endl;
	cout << endl << endl << " Start of new stuff" << endl;

	cout << "a = " << a << endl;
	cout << "b = " << b << endl;

	a.first();
	b.first();
	endit = a.size() / 2;
	for (int i = 1; i < endit; i++)
	{
		a.next();
		b.next();
	}

	a.last();
	b.last();
	a.insertAfter(100);
	a.insertBefore(99);
	cout << " Test last " << endl;
	cout << "a = " << a << endl;
	cout << "b = " << b << endl;

	cout << "New position in Obj 'a' position = " << a.size() / 2 << endl;

	for (int i = 1; i<8; i++)
	{
		a.erase();
		b.replace(i);
	}

	cout << "Modified Object 'a' " << endl;
	cout << "List a: " << a << endl;

	List c(b);
	cout << "Copy Constructor c(b)" << endl;
	cout << "List b : " << b << endl;
	cout << "List c : " << c << endl;

	if (c == b)
		cout << "List c & b are equal" << endl;
	else
		cout << "List c & b are Not equal" << endl;


	List e;
	e = c;
	cout << "Object 'c' assigned to Object 'e':" << endl;
	cout << "List c : " << c << endl;
	cout << "List e : " << e << endl;

	List d;
	d = a;
	d.first();
	endit = d.size() / 2;
	for (int i = 1; i <= endit; i++)
	{
		d.next();
		d.erase();
	}
	cout << "Results after some erases: Object d  " << endl;
	cout << "List d : " << d << endl;

	d.first();
	endit = d.size();
	for (int i = 1; i < endit; d.next(), i++)
	{
		d.insertBefore(d.getElement() * 3);
		d.next();
	}
	cout << "Results after some Replaces on d " << endl;
	cout << "List d : " << d << endl;

	a.first();
	endit = a.size();
	for (int i = 1; i < endit; a.next(), i++)
	{
		a.insertBefore(a.getPos() + a.getElement());
		a.next();
		a.erase();
	}
	cout << "Results after some weird stuff on list a" << endl;
	cout << "List a : " << a << endl;

	List alist(b);
	alist.clear();
	for (int i = 1; i <= 10; i++)
		alist.insertAfter(i);
	alist.first();
	cout << "New List alist with positions above: " << endl;
	for (int i = 1; i <= 10; i++) {
		cout << setw(5) << alist.getPos();
		alist.next();
	}
	cout << endl;
	alist.first();
	for (int i = 1; i <= 10; i++) {
		cout << setw(5) << alist.getElement();
		alist.next();
	}
	cout << endl;

	List newa;
	for (int i = 1; i <= 20; i++)
		newa.insertAfter(i * 3);
	cout << "List alist and newa before swap " << endl;
	cout << " " << alist << endl;
	cout << " " << newa << endl;

	cout << endl << "  check out boundary conditions" << endl;
	List sq;
	cout << "number of elements in empty sq list = " << sq.size() << endl;
	sq.first();
	sq.erase();
	cout << "empty sq values " << sq << endl;
	sq.insertBefore(999);
	cout << "sq values " << sq << endl;
	sq.next(); sq.next();
	cout << "sq.getElement() = " << sq.getElement() << endl;
	cout << "sq values " << sq << endl;
	system("pause");   //This statement not needed in code blocks, just VS.
	return 0;
}