/* Filename:  readfile2.cpp

   Author:  Br. David Carlson; Br. Isidore Minerd

   Date:  January 8, 2000

   Modified:  June 26, 2000; August 22, 2001, October 26, 2004; July 16, 2009

   This program reads floating point numbers from the text file
   readfile.txt and finds and prints their average.  The text
   file readfile.txt should have the numbers on separate lines or
   separated by blank space.
   
   Tested with:
      Microsoft Visual C++ 6.0
      Microsoft Visual C++ .NET
      Microsoft Visual Studio 2008
      g++ under Linux
*/

#include <iostream>
#include <fstream>   // needed for files
using namespace std;

// Function prototype:
void ProcessFile(fstream & fs);


int main(void)
   {
   fstream InFile;

   InFile.open("readfile.txt", ios::in);
   if (InFile.fail())
      {
      cout << "Could not open readfile.txt" << endl;
      exit(1);
      }
      
   ProcessFile(InFile);

   InFile.close();
   return 0;
   }
   

/* Given:  fs   A text file of floats, one per line, already opened for input.
   Task:   To read the floats from fs and compute and print their average.
   Return: Nothing.
*/   
void ProcessFile(fstream & fs)
   {
   float Num, Total;
   int Count;
      
   Count = 0;
   Total = 0.0;

   fs >> Num;

   while (! fs.fail())
      {
      Total = Total + Num;
      Count++;
      fs >> Num;
      }

   if (Count > 0)
      cout << "Average is " << Total / Count << endl;
   else
      cout << "No data given" << endl;   
   }