C++ Sorting .txt files using a template

I am trying to write a program that takes 3 input .txt files, uses a template to sort the files, and write the sorted data to 3 output files. The 3 input .txt files I am trying to sort are IntFile.txt, FloatFile.txt, and QUOTES.txt. The type of data stored in the files is integers, doubles, and strings, respectively. Right now I am trying to just get the IntFile.txt to sort and am having trouble reading the .txt file and saving it to an array to send to my template to sort. I cannot figure out a way to stop the for loop once it reads the last data from the file. The program I have written thus far is

`#include <iostream>
 #include <fstream>
 #include <iomanip>
 #include <string>
 #include <cstdlib>
 #include "sorting.h"
 using namespace std;

 int main()
 {

    ifstream inNumbers("IntFile.txt");
    ifstream inFloaters("FloatFile.txt");
    ifstream inWords("QUOTES.txt");
    ofstream outNumbers("SortedInt.txt");
    ofstream outFloaters("SortedFloat.txt");
    ofstream outWords("SortedQuotes.txt");

    int i, length = 0;
    int data[100];

    if (!inNumbers)
    {
        cerr << "IntFile.txt file could not be opened" << endl;
        exit(1);
    }

    if (!inFloaters)
    {
        cerr << "FloatFile.txt file could not be opened" << endl;
        exit(1);
    }

    if (!inWords)
    {
        cerr << "QUOTES.txt file could not be opened" << endl;
        exit(1);
    }

    for (i = 0; data[i] ; ++i)
    {
        inNumbers >> data[i];
        length += 1;
    }

    sorting(data[100], length);

 }`