#include <iostream>
#include <string>
using namespace std;
											// * define as pointer | & address of... to give a pointer a location to access, shows address of a value
struct TListenKnoten

{
	int data;				//stored value of given node
	TListenKnoten* next;		//stores the address of a following TLi structure node,
	TListenKnoten* prev;	// new address value to store the previous value
};

void hinten_anfuegen(TListenKnoten* &anker,int &prevpointer , const int wert)			//needs the structure address of anker and a value to assign
{
	TListenKnoten* neuer_eintrag = new TListenKnoten;      //reserves memory from the heap for the next struct, neuer_eintrag being the next node to be worked on
	TListenKnoten* prev_eintrag = nullptr;

	neuer_eintrag->data = wert;							//allocating the three values for the node, its own address, the data it carries and the next point it references
	neuer_eintrag->next = nullptr;
	neuer_eintrag->prev = prevpointer;

												//new data point prev, to acces the node infront of it, anker being the value in front of it
	if (anker == nullptr)
	{													//Anker as the "left" end of the list, the latest added value. Opposed to the nullpointer as the right end
		anker = neuer_eintrag;
		anker->prev = nullptr;
	}												//this if gets called for the first added value to the list
	else											//the else gets called for every subsequent addition to the node list, it assigns the proper values to the anker
	{
		TListenKnoten* ptr = anker;				//anker can be seen as the current "selected" position of the node list, anker gets update to the latest value
		while (ptr->next != nullptr)			//a while loop to go through the entire list, checking if the next value is the nullpointer
			ptr = ptr->next;					//updates the value to check for the next one
			ptr->next = neuer_eintrag;			//after reaching the end of the list, with the next one being the nullptr, the new node is added between the nullptr and the previous node


	}

}

string liste_als_string(TListenKnoten* anker)
{
	string resultat = "";
	if (anker == nullptr)
		return "Leere Liste.";
	else
	{
		resultat += "[ ";
		TListenKnoten* ptr = anker;								// runs through all the list nodes, with ptr being the current TListenKnoten struct
		while (ptr != nullptr)
		{
			resultat += std::to_string(ptr->data);
			if (ptr->next != nullptr)						// if the next node is not the "right" end of the list, aka the nullpointer,
				resultat += " , ";
			else
				resultat += " ";							//else add an empty space to end the loop
				ptr = ptr->next;							// goes to the next node by updating ptr. Giving it the address of the next node
		}
		resultat += "]";
	}
	return resultat;
}

void liste_ausgeben(TListenKnoten* anker)				// outputting the values of the entire list, starts with addrss Anker to the latest node member
{
	cout << liste_als_string(anker) << endl;
}

void liste_ausgeben_rueckwaerts(TListenKnoten* anker)
{
	if (anker == nullptr)
		cout << "Leere Liste.";

	string resultat = "";

	TListenKnoten* ptr = anker;
	while (ptr != nullptr)
	{
		ptr = ptr->next;
		if (ptr->prev == nullptr)
		{
			resultat += "[ ";

			while (ptr != anker)
			{
				resultat += std::to_string(ptr->data);
				if (ptr->prev != nullptr)
					resultat += " , ";
				else
					resultat += " ";
				ptr = ptr->prev;
			}
			resultat += "]";
		}
		cout << resultat << endl;
		}
	}



int main()
{
	const int laenge = 10;
	TListenKnoten* anker = nullptr;					//the address for the structure called anker is given the nullpointer address value
	int* prevpointer = nullptr;
	liste_ausgeben(anker);
	liste_ausgeben_rueckwaerts(anker);

	for (int i = 0; i < laenge; i++)
		hinten_anfuegen(anker,prevpointer, i);

	liste_ausgeben(anker);
	liste_ausgeben_rueckwaerts(anker);
	system("PAUSE");
	return 0;
}#include <iostream>
#include <string>
using namespace std;
											// * define as pointer | & address of... to give a pointer a location to access, shows address of a value
struct TListenKnoten

{
	int data;				//stored value of given node
	TListenKnoten* next;		//stores the address of a following TLi structure node,
	TListenKnoten* prev;	// new address value to store the previous value
};

void hinten_anfuegen(TListenKnoten* &anker,int &prevpointer , const int wert)			//needs the structure address of anker and a value to assign
{
	TListenKnoten* neuer_eintrag = new TListenKnoten;      //reserves memory from the heap for the next struct, neuer_eintrag being the next node to be worked on
	TListenKnoten* prev_eintrag = nullptr;

	neuer_eintrag->data = wert;							//allocating the three values for the node, its own address, the data it carries and the next point it references
	neuer_eintrag->next = nullptr;
	neuer_eintrag->prev = prevpointer;

												//new data point prev, to acces the node infront of it, anker being the value in front of it
	if (anker == nullptr)
	{													//Anker as the "left" end of the list, the latest added value. Opposed to the nullpointer as the right end
		anker = neuer_eintrag;
		anker->prev = nullptr;
	}												//this if gets called for the first added value to the list
	else											//the else gets called for every subsequent addition to the node list, it assigns the proper values to the anker
	{
		TListenKnoten* ptr = anker;				//anker can be seen as the current "selected" position of the node list, anker gets update to the latest value
		while (ptr->next != nullptr)			//a while loop to go through the entire list, checking if the next value is the nullpointer
			ptr = ptr->next;					//updates the value to check for the next one
			ptr->next = neuer_eintrag;			//after reaching the end of the list, with the next one being the nullptr, the new node is added between the nullptr and the previous node


	}

}

string liste_als_string(TListenKnoten* anker)
{
	string resultat = "";
	if (anker == nullptr)
		return "Leere Liste.";
	else
	{
		resultat += "[ ";
		TListenKnoten* ptr = anker;								// runs through all the list nodes, with ptr being the current TListenKnoten struct
		while (ptr != nullptr)
		{
			resultat += std::to_string(ptr->data);
			if (ptr->next != nullptr)						// if the next node is not the "right" end of the list, aka the nullpointer,
				resultat += " , ";
			else
				resultat += " ";							//else add an empty space to end the loop
				ptr = ptr->next;							// goes to the next node by updating ptr. Giving it the address of the next node
		}
		resultat += "]";
	}
	return resultat;
}

void liste_ausgeben(TListenKnoten* anker)				// outputting the values of the entire list, starts with addrss Anker to the latest node member
{
	cout << liste_als_string(anker) << endl;
}

void liste_ausgeben_rueckwaerts(TListenKnoten* anker)
{
	if (anker == nullptr)
		cout << "Leere Liste.";

	string resultat = "";

	TListenKnoten* ptr = anker;
	while (ptr != nullptr)
	{
		ptr = ptr->next;
		if (ptr->prev == nullptr)
		{
			resultat += "[ ";

			while (ptr != anker)
			{
				resultat += std::to_string(ptr->data);
				if (ptr->prev != nullptr)
					resultat += " , ";
				else
					resultat += " ";
				ptr = ptr->prev;
			}
			resultat += "]";
		}
		cout << resultat << endl;
		}
	}



int main()
{
	const int laenge = 10;
	TListenKnoten* anker = nullptr;					//the address for the structure called anker is given the nullpointer address value
	int* prevpointer = nullptr;
	liste_ausgeben(anker);
	liste_ausgeben_rueckwaerts(anker);

	for (int i = 0; i < laenge; i++)
		hinten_anfuegen(anker,prevpointer, i);

	liste_ausgeben(anker);
	liste_ausgeben_rueckwaerts(anker);
	system("PAUSE");
	return 0;
}