Array-Linked List Problem

I was wondering how the format for converting a structured Array (in which the data is loaded from a text file) to a Linked List would look. And how i would edit the menu functions that run my program.

code:
(IN MAIN.CPP)

Code:

#include <iostream>
#include <fstream>
#include <iomanip>
#include <sstream>
#include <string>
#include <stdlib.h>
#include "StudentRec.h"
#include "DatabaseIO.h"
#include "RecordProcessing.h"




using namespace std;
//Global Declaration


StudentRec students[ISIZE];
ifstream inFile;
int arraysize;


int main()
{
string buffer;
int selection = 0;
const int NOTOK = 1;

read_file(students, "studentrecord.txt");
SortStudentArray(students, ISIZE);

while(selection != 5)
{
cout << "Please choose" << endl <<
"(1) Add a student record" << endl <<
"(2) Delete a student record" << endl <<
"(3) Find a student's information" << endl <<
"(4) Display all information in the database" << endl <<
"(5) Exit Program" << endl;
cin >> selection;

if(!cin)
{
cout << "You have entered an invalid selection, Terminating program!..." << endl;
exit(NOTOK);
}

if(selection < 0 or selection > 5)
{
cout << "Invalid selection, Terminating program!..." << endl;
exit(NOTOK);
}

if(selection == 1)
{
add_a_record(students);
}

if(selection == 2)
{
StudentRec dummy;
delete_a_record(dummy);
}

if(selection == 3)
{
string ID;
cout << "Please enter Student ID: ";
cin >> ID;
int position;
position = BinarySearch(students, 0, arraysize, ID);
if (position == -1)
{ 
cout << "Not Found" << endl;
}
else
cout << students[position].Name << "\t";
cout << students[position].ID << "\t";
cout << students[position].GPA << endl;
}

if(selection == 4)
{
display_data(students);
}

if(selection == 5)
{
save_database(students, "studentrecord.txt");
}
} //Ends While loop

} //Ends Int main

(IN STUDENTREC.H)

using namespace std;
struct StudentRec
{
string Name;
string ID;
double GPA;
};

struct StudentListNode
{
StudentRec students;
StudentListNode *next;
};

const int ISIZE = 100;

****(Function definitions left out)*****

suppose you have "N" student records, stored in array "stu[]", now you want a linked list with "head" as the pointer to the first element of the list, then

Code:

StudentListNode *ptr = head = new StudentListNode();
ptr->students = stu[0];
for(int i=1; i<N; i++){
  ptr -> next = new StudentListNode();
  ptr = ptr -> next;
  ptr -> students = stu[i];
}
ptr -> next = 0;

It's pretty standard. But if you want to use a list, you could always use STL's list, instead of writing your own.