Implementing Double Linked Lists as an Array of Pointers in C++

#include <iostream> 
#include <fstream>
#include <iomanip>

using namespace std;  

const int MAX_CELLS = 10;        
const int UNIQUE_FIVE_DIGIT = 5; 

struct node
{
    node* prev;                                            
    node* next;                                        
    int   data;                                        
};           
/////////////////////////////////////////////////////////////////////
int main(int argc, char* argv[]) 
{
    ifstream inFile;                      
    node *lists[MAX_CELLS] = { NULL };      
    int count = -1;                       
    bool result = true;                     

    do 
    {

        if ( argc != 2 ) 
        {
            cout << "Command line arguments not valid!" << endl << endl;
            result = false;
        }   

        if ( !argv[1] ) 
        {
            cout << "The command line arguments does not specify any filename!" << endl; 
            result = false;
        }           

        inFile.open(argv[1]);

        if ( !inFile ) 
        {
            cout << "The input data file does not exist or cannot be opened!" << endl;
            result = false;
        }   

        if ( result )
        {
            cout << "Results for input file " << argv[1] << ":" << endl;
            ReadInFile(inFile, lists, count);   

            result = false;  
        }

    } while ( result );

    system("PAUSE");  
    return 0;
}
///////////////////////////////////////////////////////////////////
void ReadInFile(ifstream& inFile, node* arrayPtr[], int& count) 
{
    int number = 0;
    int newNumber = 0;
    int countResult = 0;
    node* p = new node;

    while ( inFile )   
    {

        inFile >> number;
        newNumber = number / 10000; 

        if ( !isDuplicate(arrayPtr[newNumber], number) )
        {
                arrayPtr[newNumber] = prepend( arrayPtr[newNumber], number );
                p = arrayPtr[newNumber];
        }

        count++;
    }

    for (int count = 0; count < 10; count++)
    {    
        arrayPtr[count] = p;
        countResult = counting(p);
    }

    cout << setw(7) << count << " total integers read from file" << endl << endl;

    inFile.close();    

    cout << "The " << countResult << " unique integers beginning with digit " << newNumber <<" were " << endl;

    displayIt(p, countResult);
}
/////////////////////////////////////////////////////////////////////
void displayIt(node* p, int count) 
{
    cout << setw(14); 
    print_list(p);
    cout << endl;
}
/////////////////////////////////////////////////////////////////////
bool isDuplicate(node* top, int number) 
{

    while( top != NULL )
    {

        if( top->data==number )
            return true;

        top = top->next;
    } 

    return false;
}
/////////////////////////////////////////////////////////////////////
node* prepend(node* beginning, int number) 
{
    node* p = new node;

    p->data = number;
    p->prev = NULL;
    p->next = beginning;

    if( beginning != NULL )
    {
        beginning->prev = p;
    }

    return p;
}
/////////////////////////////////////////////////////////////////////
void print_list( node* beginning ) 
{    

    for( node *p=beginning; p != NULL; p=p->next )
    {
        std::cout << p->data;

        if( p->next != NULL )
        {
            std::cout << " ";
        }

    }      
}
/////////////////////////////////////////////////////////////////////
int counting( node* beginning ) 
{
    int count(0);

    for( node *p=beginning; p != NULL; p=p->next )
    {
        ++count;
    }

    return count;
}