#include<iostream>
#include<fstream>
#include <conio.h>
 
using namespace std; 
 
struct node
  {  
     string firstName;    // firstName  letters
 
     string lastName;     //lastName letters
 
     string  telnumber;          // Telephone number
 
     string housenumber;       // fax number
 
     string city;             // city
 
     string state;            //state
 
     string zipcode;          //zipcode
 
     node *link;        // Pointer to next node
  };
 
node *head = NULL;
 
 
//Function to add a node to the list
//Sets the list head to newNode if list is empty
//Add the newNOde to the next position in the list if list is not empty
void add_node_at_end (node & newNode)
  {  
  node *temp, *temp2;   // Temporary pointers
 
     // fill the newNOde with the incoming data
     temp = new node;
 
     temp->firstName = newNode.firstName;
 
     temp->lastName = newNode.lastName;
 
     temp->telnumber = newNode.telnumber;
 
     temp->housenumber = newNode.housenumber;
 
    temp->city = newNode.city;
 
     temp->state = newNode.state;
 
     temp->zipcode = newNode.zipcode;
 
     temp->link = NULL;
 
     // Add this node to the list
     if (head == NULL)
         head = temp;
     else
       { 
            temp2 = head;
            // if the list not empty!
     while (temp2->link != NULL)
           {  temp2 = temp2->link;
           // Move to next link in chain
           }
         temp2->link = temp;
 
       }
}
 
////////////////////////////////////////////
//Function ito displays the output file
////////////////////////////////////////////
 
void DisplayList(ofstream & outfile)
{
  node * temp = head;
 
do
  {  if (temp == NULL)
       cout << "End of list" << endl;
     else
       {  // Display details for what temp points to
          outfile << "firstName : " << temp->firstName << endl;
 
          outfile << "lastName : " << temp->lastName << endl;
 
          outfile << "telnumber : " << temp->telnumber << endl;
 
          outfile << "housenumber : " << temp->housenumber << endl;
 
          outfile << "city : " << temp->city << endl;
 
          outfile << "state : " << temp->state << endl;
 
          outfile << "zipcode : " << temp->zipcode << endl;
 
          outfile << endl;       // Blank line
 
          // Move to next node (if present)
          temp = temp->link;
       }
  }
while (temp != NULL);
 
  }
 
 
//Deleting node at head
  void delete_start_node()
   { 
     node *temp;
     temp = head;
     head = head->link;
     delete temp;
   }
 
    //deleting at end
 
   void delete_end_node()
   { 
     node *temp1, *temp2;  // Temporary pointers
 
     //Deleting a node at the end of the list
   if (head == NULL)
     cout << "The list is empty!" << endl;
   else
    { 
      temp1 = head;
   if (temp1->link == NULL)     
       { 
         delete temp1;
         head = NULL;
       }
   else
       { 
         while (temp1->link != NULL)
       { 
          temp2 = temp1;
          temp1 = temp1->link;
       }
         delete temp1;
         temp2->link = NULL;
       }
    }
 }
 
void add_node_at_start (node & newNode)
{
  node * temp = 0;   // Temporary pointers
 
     // Reserve space for new node and fill it with data
     temp = new node;
 
      temp->firstName = newNode.firstName;
 
      temp->lastName = newNode.lastName;
 
      temp->telnumber = newNode.telnumber;
 
      temp->housenumber = newNode.housenumber;
 
      temp->city = newNode.city;
 
      temp->state = newNode.state;
 
      temp->zipcode = newNode.zipcode;
 
 
      temp->link = head;
 
       head = temp;
}   
 
 
void add_in_middle(node & newNode)
     {
          node * newNodePtr = 0;   // Temporary pointers
 
     // Reserve space for new node and fill it with data
     newNodePtr = new node;
 
 
  newNodePtr->firstName = newNode.firstName;
 
      newNodePtr->lastName = newNode.lastName;
 
      newNodePtr->telnumber = newNode.telnumber;
 
      newNodePtr->housenumber = newNode.housenumber;
 
      newNodePtr->city = newNode.city;
 
      newNodePtr->state = newNode.state;
 
      newNodePtr->zipcode = newNode.zipcode;
 
     newNodePtr->link= head->link;
 
     head->link =newNodePtr;
 
     }
 
void delete_in_middle ()
{
     node * temp;  // Temporary pointer
 
     // check to see if the list is empty
 
     if (head!= NULL)
     {                     
        // check to see if there is more than 1 node in the list
 
        if (head->link != NULL)
        {                         
           temp= head->link->link ;
 
           delete  head->link;
 
           head->link = temp;
         }
     } 
}
 
int main(void) 
{    
   node inputNode;
 
   ifstream infile;  // input file
 
   infile.open("c:\\pbinput.txt");
 
   if (!infile) 
   {
      cerr << "Unable to open file inputfile.txt";
 
      exit(1);   // call system to stop
   }
 
   ofstream outfile;
 
   outfile.open("outputfile.txt");
 
   if (!outfile) 
   {
      cerr << "Unable to open file outputForPow.txt";
 
      exit(1);   // call system to stop
   }
 
   outfile << "This file contains the input and output for the Power function " << endl << endl;
 
 
   int i = 0;
 
     while (!infile.eof())
     {
         infile >> inputNode.lastName >> inputNode.firstName >> inputNode.telnumber >> inputNode.housenumber >> inputNode.city >> inputNode.state >> inputNode.zipcode ;
 
         outfile << "Last name: " << inputNode.lastName << " first name: " <<  inputNode.firstName << " tel number: " <<  inputNode.telnumber << " house number: " <<  inputNode.housenumber << " city: " << inputNode.city << " state : " <<  inputNode.state << " zip code: " <<  inputNode.zipcode  << endl;
 
         if ((i % 3) == 0)
         {            
            outfile << "Adding to end of list " << endl;
 
            add_node_at_end (inputNode);
         }
         else if ((i %3) == 3)
         {
             outfile << "Adding to beginning of list " << endl;
 
             add_node_at_start (inputNode);
         }    
         else
         {
            outfile << "Adding to the middle of list " << endl;
 
            add_in_middle(inputNode);
         }
 
         i++;
 
 
     }
 
    outfile << "displaying list after reading input: " << endl;
 
    DisplayList(outfile);
    getch();
    outfile << "displaying list after deleting first node: " << endl;
 
    delete_start_node();
 
    DisplayList(outfile);
    getch();
    outfile << "displaying list after deleting last node: " << endl;
 
    delete_end_node();
 
    DisplayList(outfile);
    getch();
    outfile << "displaying list after deleting a node in the middle of the list: " << endl;
 
    delete_in_middle();
 
    DisplayList(outfile);     
    getch();   
 
    infile.close();
 
    outfile.close();
 
    return(1);
}

while (!infile.eof())
{
        infile >> inputNode.lastName >> ....

while (infile >> inputNode.lastName >> .........)
{
     //processing begins