How to transfer an array to a class array?

[Tiger58]

We had a lab in my class today where we had to send file data (20 elements) into a class array (not an array of a class, but an array IN the class). The following is the way in which I did that:

Header File:

#ifndef LABFOUR_H
#define LABFOUR_H
#include <iostream>
using namespace std;

//Class is defined
class SearchCount
{
  private:
    //Declares the number of elements for the class array
    static const int SIZE=20;
    int number[SIZE];
    int counter;
  public:
    //Constructor
    SearchCount()
    {
        //Initializes the array elements to 0
        for(int i=0;i<SIZE;i++)
            number[i]=0;

        counter=0;
    }
    
    //Mutator Functions
    void setNumber(int n)
    { 
        number[counter]=n;
        counter++;
    }
    void setCount(int co)
    { counter=co; }
    
    //Accessor Functions
    int getNumber(int c)
    { return number[c]; }
    int getCount()
    { return counter; }
    
};
#endif 

C++ File

/*This program allows the user to search for a number using either linear
or binary means (Bubble and Selection sorting for binary)*/
#include <iostream>
#include <fstream>
#include "LabFour.h"
using namespace std;

//Simple functions to read file and display menu
void readFile(SearchCount[],int);

//**************************************************
//Main function
int main()
{
    //Class object array is declared
    const int NUM=3;
    SearchCount order[NUM];
    int option,
        value,
        //Holds values received from class functions
        tempInt;

    //Reads file
    readFile(order,NUM);

    return 0;
}

//**************************************************
/*Reads the file and saves the values equally among the
object array*/
void readFile(SearchCount order[], int NUM)
{
    int tempInt;

    ifstream readFile;
    readFile.open("numbers.txt");
    if(!readFile)
    {
        cout<<"Error opening file."<<endl;
        cout<<"Press enter to exit the program."<<endl;
        cin.get();
        exit(0);
    }

    while(readFile>>tempInt)
    {
        //Assigns tempInt to every array element before reading the next number
        //Loops depend on the size of the array
        for(int i=0;i<NUM;i++)
        {
            order[i].setNumber(tempInt,i);
        }
    }

    //Closes file
    readFile.close();
}

Mind any things that seem out of place, I cut out what it is that I wanted to change so this is not the whole program.

The thing is, when I asked the professor about it he said it was fine. But when I asked him if I could have done it better, he said it would have been easier to just read and transfer the whole array from the main file. I am not sure what he meant by that and I didn't have time to ask him at the end of the class. Can anyone enlighten me on it, or perhaps suggest a better way of doing this? I know my own way is faulty because if they decided to initialize some numbers, it would get screwed.

Thank in advance and very much appreciated.