TemplList

TemplList.h

#pragma once

#include <iostream>

using namespace std;

template <typename T>
class TemplList
{
public:
	struct Elem
	{
		T data;
		Elem* next;
		Elem* prev;
	};

private:
	Elem *Head, *Tail;
	int length;

public:
	TemplList()
	{
		Head = Tail = nullptr;
		length = 0;
	}

	~TemplList()
	{
		DelAll();
	}

	int GetLength()
	{
		return length;
	}

	void AddTail(int n)
	{
		Elem* temp = new Elem();
		temp->next = nullptr;
		temp->data = n;
		temp->prev = Tail;

		if (Tail != nullptr) Tail->next = temp;

		if (length == 0) Head = Tail = temp;
		else Tail = temp;

		length++;
	}

	void AddHead(int n)
	{
		Elem * temp = new Elem();
		temp->prev = nullptr;
		temp->data = n;
		temp->next = Head;

		if (Head != nullptr) Head->prev = temp;

		if (length == 0) Head = Tail = temp;
		else Head = temp;

		length++;
	}

	void Del(int pos)
	{
		if (pos < 1 || pos > length)
			throw "Incorrect position";

		int i = 1;
		Elem * Del = Head;
		while (i < pos)
		{
			Del = Del->next;
			i++;
		}

		Elem * PrevDel = Del->prev;
		Elem * AfterDel = Del->next;

		if (PrevDel != nullptr && length != 1)
			PrevDel->next = AfterDel;

		if (AfterDel != nullptr && length != 1)
			AfterDel->prev = PrevDel;

		if (pos == 1) Head = AfterDel;
		if (pos == length) Tail = PrevDel;

		delete Del;

		length--;
	}

	void DelAll()
	{
		while (length != 0)
		{
			Del(1);
		}
	}

	Elem* GetElem(int pos)
	{
		if (pos < 1 || pos > length)
			throw "Incorrect position";

		Elem *temp = Head;

		int i = 1;
		while (i < pos && temp != nullptr)
		{
			temp = temp->next;
			i++;
		}

		if (temp == nullptr) return nullptr;
		return temp;
	}

	void ShowList()//this function is used for debugging, possible to use only if T is of basic type or operator<< is overloaded
	{
		if (!length)
			return;

		Elem* temp = Head;

		while (temp)
		{
			cout << temp->data << " ";
			temp = temp->next;
		}

		cout << endl;
	}

};