//This file is only to demonstrate C++ functions work
//Purpose: To show that this function can be called in a driver program
void hello()
// Pre:  Always works
// Post: Changes nothing but outputs a message
// Returns: Nothing useful
{  
   cout << "Hello, World\n";
   return ;
}  // end hello


//Purpose: To demonstrate call by value
int mad(
   int x // IN: An integer value supplied by the main program.
  )
// Pre:  x must be a valid int
// Post: Does not change any part of calling program
// Returns: Returns one more than the given value of x
{
   x = x + 1;
   return x;
}  // end mad

//Purpose: To demonstrate call by reference
int sad(
   int & x // INOUT: An int VARIABLE supplied by the main program.
  )
// Pre:  x must be a valid int variable
// Post: The variable that x refers to is increased by 1
// Returns: Returns one more than the given value of x
{
   x = x + 1;
   return x;
}  // end sad