C++ Program to implement Infinite Arrays

#include <iostream>
#include <cstdlib>
#include <assert.h>

#include "ia.h"

int& i_arr::operator [] (const unsigned int index)
{
    class i_arr *ptrc;
    unsigned int i; 
    ptrc = this;
    i = index;

    while (i >= BSIZE) {
        if (ptrc->next == NULL) {
            ptrc->next = new i_arr;
            if (ptrc->next == NULL) {
                std::cerr << "Error:Out of memory\n";
                exit(8);
            }
        }
        ptrc = ptrc->next;
        i -= BSIZE;
    }
    assert(i >= 0);
    assert(i < 
            sizeof(ptrc->data)/sizeof(ptrc->data[0]));
    return (ptrc->data[i]);
}

i_arr::~i_arr(  )
{
    if (next != NULL) {
       delete next;
       next = NULL;
    }
}