//----------------------------------------------------------------------
//
// functions.cpp
//
// This program gives some example functions.
//
// Written by:  Simon Parsons
//
// Last modified: 4th October

#include <iostream>

using namespace std;

// sumUp()
//
// A simple function that takes two integers as its arguments and
// returns an integer.

int sumUp (int a, int b){
  int c;
  c = a + b;
  return c;
}

// divvyUp()
//
// This function takes two integers as its arguments and returns a
// double

double divvyUp (int a, int b){
  return (double) a / b;
}

// isEven()
//
// This function has a bit more to it. Oh, and it returns a bool.

bool isEven (int a){
  if ((a % 2) == 0){
    return true;
  }
  else {
    return false;
  }
}

// printValues()
// 
// And now we have a function that doesn't return a value

void printValues(int a, double b){
  cout << "We have an integer " << a << " and a double " << b << endl;
}

// Now we start main() from which we call the functions

int main() 
{

  // Declare variables

  int x;   
  int y;
  int z;

  // Initialize variables

  x = 0;
  y = 0;

  // Now enter values

  cout << "Please enter a value for x: ";
  cin >> x;
  cout << "and now a value for y: ";
  cin >> y;
  cout << "Thanks!" << endl << endl;
  
  // Functions return values, so we can use them like this:

  z = sumUp(x, y);
  cout << z << endl;

  // and like this:

  cout << divvyUp(x, y) << endl << endl;

  // We can also use them in more complex constructions:

  if(isEven(x)){
    printValues(z, divvyUp(x, y));
  }
  else {
    cout << divvyUp(y, x) << endl;
  }

  return 0;
    
} // end of main()