text: ///////////////////////////////////////////////////////////////////////////////
  //  Copyright Christopher Kormanyos 2019.
  //  Distributed under the Boost Software License,
  //  Version 1.0. (See accompanying file LICENSE_1_0.txt
  //  or copy at http://www.boost.org/LICENSE_1_0.txt)
  //
  
  // appendix0a_03-001_function_overloading.cpp
  
  #include <iostream>
  
  // The area of a rectangle.
  float area(const float& length,
             const float& width)
  {
    return length * width;
  }
  
  // The area of a circle.
  float area(const float& radius)
  {
    constexpr float pi = 3.14159265358979323846F;
  
    return (pi * radius) * radius;
  }
  
  int main()
  {
    std::cout << "area rectangle: " << area(1.2F, 3.4F)  << std::endl;
    std::cout << "area circle   : " << area(1.234F)      << std::endl;
  }
  