// File: readAndPrintStruct.cpp
// Example of opening, reading, and printing a file of integers
// Now, with a struct to hold the data

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

using namespace std;

int const MAX=10;

// A partially filled array (can have 0 to 10 elements
// An array along with an int to store how many items are in use
struct Data {	
  int list[MAX];	
  int items;
};

// Opens file designated by user. Returns whether file was opened.
// Parameters:
// inf		import/export
bool openFile(ifstream &inf);

// Read elements in file and place in array
// Parameters:
// inf		import/export
// TheData	output only 
// max		Note that with a global const, this parameter is not retained.
void readFile(ifstream &inf, Data &TheData);

// Print the integers read
// TheData	import only 
// Could there be any advantage to passing TheData by reference?
void printFileContents(Data TheData);

int main()
{ ifstream inf;
  Data TheData;
  if (openFile(inf)) {
    readFile(inf,TheData);
    printFileContents(TheData);
  }
}

// Opens file designated by user. Returns whether file was opened.
// Parameters:
// inf		import/export
bool openFile(ifstream &inf)
{ string fileName;
  cout << "Enter File Name >";
  cin >> fileName;
  inf.open(fileName.c_str());
  return(inf);   // returns true if file found and opened
}

// Read elements in file and place in array
// Parameters:
// inf		import/export
// TheData	export only 
// max		Note that with a global const, this parameter is not retained.
void readFile(ifstream &inf, Data &TheData)
{ int value;
  TheData.items=0;
  while (TheData.items<MAX && inf >> value)
    TheData.list[TheData.items++]=value;
}

// Print the integers read
// TheData	import only 
// Could there be any advantage to passing TheData by reference?
void printFileContents(Data TheData)
{ for (int i=0;i<TheData.items;i++)
    cout << setw(3) << i << ":" << TheData.list[i] << endl;
}