doubly linked list problem

[DocCeaser]

My problem is creating the linked list. I'm trying to read the data for students from a file and store it in the list. I don't know how to store multiple pieces of data in a node. This is what I have.

#include <iostream>
#include <fstream>
using namespace std;
struct studentType
{
    string studentID;
    string firstname;
    string lastname;
    double salary;
    studentType *next;
    studentType *back;
};    
void createList(studentType* first, studentType* last);
void printList(studentType* first);
void printListBack(studentType* last);
void insertFront(studentType* first);
void insertBack(studentType* last);
ifstream infile;
int main()
{
    studentType *first, *last;
    string ID, fname, lname;
    int number;
    createList(first, last);
    
    
    
    system("PAUSE");
    return 0;
}
void createList(studentType*& first, studentType*& last)
{
    studentType *newNode;
    string ID, fname, lname;
    int number;
    
   
    first = NULL;
    last = NULL;
 
 infile.open("students.txt");
 while(infile)
     {
    for(int i=0; i<4; i++)
     {
newNode = new studentType;
infile>>studentID>>firstname>>lastname>>salary;
newNode->studentID=ID;
newNode->firstname=fname;
newNode->lastname=lname;
newNode->salary=number;    
newNode->next = NULL;
newNode->back = NULL;
      }
         if (first == NULL)
         {
            first = newNode;
            last = newNode;
         }
         else
         {
           last->link = newNode;
           last = newNode;
         }
        
     } // end of while-loop
        
}

[Azagaros]

I am going to assume that a line in your data file looks like:

001 Mickeal Hodgekins 10.00
002 Jeana Goggie 11.11

Please let me know if I am correct.

If this is the case I would expect:

#include <iostream>
#include <fstream>

using namespace std;

struct studentType
{
    string studentID;
    string firstname;
    string lastname;
    double salary;
    studentType *next;
    studentType *back;
};
 
studentType* CreatList();
{
    studentType *listHead = NULL;
    studentType *currentNode = NULL;
    studentType *newNode = NULL;

    infile.open("students.txt");
    while(infile)
    {
         // this assumes the list is sequential in the file.

          newNode = new studentType;
          infile >> newNode->studentID;
          infile >> newNode->firstname;
          infile >> newNode->lastname;
          infile >> newNode->salaray;
          NewNode->next = null;
          newNode->back = currentNode;
          
          // keep track of this node for the next pass of data for the back pointer.
          currentNode = newNode;
          if(listHead == NULL)
          {
              // build the empty list
              ListNead = newNode;
          }
          else
          {
              // find the tail of the list and append;
              studenttype *pSearch = listHead;
              while(pSearch->next)
              {
                  pSearch = pSearch->next;
               }
               pSearch->next= newNode;
           }
     } // while on the file.

     return listHead;
}

int main()
{

       studentType *pListhead = CreateList();
       studentType *pCurrentNode = pListHead;
      
       if(pListHead)
       {
            while(pCurrentNode->next)
            {
                 cout << pCurrentNode->studentID << "\t";
                 cout << pCurrentNode->firstname << "\t";
                 cout << pCurrentNode->lastname << "\t";
                 cout << pCurrentNode->salary << endl;
                 pCurrentNode = pCurrentNode->next;
            }
            //pCurrentNode should be at the bottom of the list when I hit here.
            cout << endl << "Backwards" << endl;
           
            while(pCurrentNode->back)
            {
                 cout << pCurrentNode->studentID << "\t";
                 cout << pCurrentNode->firstname << "\t";
                 cout << pCurrentNode->lastname << "\t";
                 cout << pCurrentNode->salary << endl;
                 pCurrentNode = pCurrentNode->back;
            }
       }
       return 0;
}

[DocCeaser]

A line in the data file looks a little more like this2214 Derek Anderson 50000
I made some changes and it runs but I can't figure out why it only outputs the last line of the file?

#include <iostream>
#include <fstream>
using namespace std;
struct studentType
{
    string studentID;
    string firstname;
    string lastname;
    double salary;
    studentType *next;
    studentType *back;
};    
void createList(studentType*& first, studentType*& last);
void printList(studentType* first);
void printListBack(studentType* last);
void insertFront(studentType* first);
void insertBack(studentType* last);
ifstream infile;
int main()
{
    studentType *first, *last;
   
    
    createList(first, last);
    printList(first);
    
    
    system("PAUSE");
    return 0;
}
void createList(studentType*& first, studentType*& last)
{
    studentType *newNode, *current;
   
    first = NULL;
    last = NULL;
    current=first;
    
 infile.open("students.txt");
 while(infile)
     {
    for(int i=0; i<4; i++)
     {
newNode = new studentType;
          infile >> newNode->studentID;
          infile >> newNode->firstname;
          infile >> newNode->lastname;
          infile >> newNode->salary;
          newNode->next = NULL;
          newNode->back= current;
          
          current=newNode;
          
      }
         if (first == NULL)
         {
            first = newNode;
            last = newNode;
         }
         else
         {
           last->next = newNode;
           last = newNode;
         }
        
     } // end of while-loop
        
}
void printList(studentType* first)
{
   studentType *current;
        current = new studentType;
        current = first;
        
        while(current !=NULL)
        {
        cout << current->studentID << "\t";
                 cout << current->firstname << "\t";
                 cout << current->lastname << "\t";
                 cout << current->salary << endl;
                 current=current->next;
        }
}

[DocCeaser]

Problem solved! Thanks for the help.