#include <iostream>
#include <stdio.h>
#include <fstream>

using namespace std;

struct node
{
	int val;
	node* next;
	node* prev;
};

node* SetE(node* &head, int k)
{
	node* e=head;
	for(int i =0; i<k-1; i++)
	{
		e=e->next;
	}
	return e;
}


void AddFirst(node* &head, int value)
{
	node* tmp = new node;
	tmp->val = value;
	tmp->next = head;

	if (head != NULL)
	{
		head = tmp;
		tmp->prev = NULL;
		tmp->next->prev = tmp;
	}
	else head = tmp;
}

void AddWhereYouWant(node *&head, node* e, int value)
{
    node *tmp = new node;
    tmp->val = value;

    if (head == e)
	{
		AddFirst(head, value);
	}
    else
	{
		e= e->prev;
 		tmp->next = e->next;
        e->next = tmp;
    }
}

void DeleteFirst(node* &head)
{
  node* tmp;
  tmp = head;
  if(tmp)
  {
    head = tmp->next;
    delete tmp;
  }
}


void DeleteWhereYouWant(node* &head, node* e)
{
  node* tmp;

  if(head == e)
  {
  	DeleteFirst(head);
  }
  else
  {
    tmp = head;
    while(tmp->next != e)
	{
		tmp = tmp->next;
	}
    tmp->next = e->next;
    delete e;
  }
}

void DisconnectAllSameValues(node* &head, int value)
{
	node* tmp;
	tmp = head;
	node* e;


	if(head!=NULL)
	{

  		if(head->val == value)
  		{
  			DeleteFirst(head);

  		}


    		while(tmp->next->next != NULL)
			{




				if(tmp->next->val==value)
				{

					e=tmp->next->next;
					tmp->next=e;
					if(tmp->next->next==NULL && tmp->next->val==value)
					{
						tmp->next=NULL;
						break;
					}
				}
				tmp = tmp->next;



			}

	}
	else cout << "Lista jest pusta lub nie ma danej wartości";
}


void ShowList(node* head)
{
	node* tmp = head;
	while (tmp != NULL)
	{
		cout << tmp->val << " ";
		tmp = tmp->next;
	}
}

void ReadFromFile(node* &head, char* Filename)
{
	ifstream plik;
	plik.open(Filename);
	int a;
	while (!plik.eof())
	{
		plik >> a;
		AddFirst(head, a);
	}

}


int main()
{
	node* head = NULL;
	ReadFromFile(head, "plik1.txt");
	ShowList(head);
	AddWhereYouWant(head, SetE(head, 4), 55);
	cout << endl;
	ShowList(head);
	DisconnectAllSameValues(head, 3);
	cout << endl;
	ShowList(head);


	system("pause");
	return 0;
}