LinkedList.cpp

#include <iostream>

class LinkedList
{
private:
	struct Node
	{
		int data;
		Node *next;

		Node(int data = 0, Node* next = NULL) : data(data), next(next)
		{}
	};

public:
	LinkedList() : head(NULL), size(0) { }
	LinkedList(const LinkedList& rhs) : head(NULL), size(0)
	{
		copy(rhs);
	}

	LinkedList& operator=(const LinkedList& rhs)
	{
		if (this == &rhs)
			return *this;

		deleteMe();
		copy(rhs);

		return *this;
	}
	
	~LinkedList()
	{
		deleteMe();
	}

	void addHead(int value)
	{
		Node* temp = new Node;

		temp->data = value;
		temp->next = head;
		head = temp;

		++size;
	}

	void addTail(int value)
	{
		addAt(size, value);
	}

	void addAt(int index, int value)
	{
		if (index == 0)
			addHead(value);
		else
		{
			Node* previous = findPrev(index);

			Node* temp = new Node;

			temp->data = value;
			temp->next = previous->next;
			previous->next = temp;
			++size;
		}
	}
	
	int removeAt(int index)
	{
		if (index >= size)
			throw "Idiot!\n";

		if (index == 0)
			return removeHead();

		Node* prev = findPrev(index);

		int data = prev->next->data;

		Node* nextNext = prev->next->next;
		
		delete prev->next;

		prev->next = nextNext;

		--size;

		return data;
	}

	bool isEmpty() const
	{
		return size == 0;
	}

	int removeHead() 
	{
		if (!head)
			throw "Basi!\n";

		int data = head->data;

		Node* next = head->next;

		delete head;

		head = next;

		--size;

		return data;
	}

	int getAt(int index)
	{
		if (index >= size)
			throw "No!\n";
		if (index == 0)
			return getHead();

		return (findPrev(index)->next->data);
	}

	int getHead()
	{
		return head->data;
	}

private:
	void copy(const LinkedList& rhs) 
	{
		const Node* rhsNode = rhs.head;

		while (rhsNode)
		{
			addTail(rhsNode->data);
			rhsNode = rhsNode->next;
		}
	}
	void deleteMe() 
	{
		while (size)
			removeHead();

		head = NULL;
	}
	Node* findPrev(int index) 
	{ 
		Node* prev = head;
		while (--index > 0)
		{
			prev = prev->next;
		}

		return prev;
	}
private:
	Node* head;
	int size;
};


int main()
{
	LinkedList list;

	for (int i = 0; i < 10; ++i)
	{
		list.addAt(i, i);
	}

	list.removeAt(9);
	list.removeAt(6);
	list.removeAt(3);

	for (int i = 0; i < 7; ++i)
		std::cout << list.getAt(i) << std::endl;

	return 0;
}