C++ source code using the Proper Numbers Library.

#include <windows.h>
#include <stdio.h>
#include "StringEx.h"
#include "Integer.h"
#include "Rational.h"
#include "Contextualize.h"

void main()
{
   {
      Integer a( 3 );
      Integer b( 2 );
      Integer c( 3452 );

      wprintf( TEXT("%s\n"), (LPCTSTR)c.Print() );

      c += b;
      wprintf( TEXT("%s\n"), (LPCTSTR)c.Print() );


      Integer d = a * b + c;
      wprintf( TEXT("%s\n"), (LPCTSTR)d.Print() );

      c--;
      wprintf( TEXT("%s\n"), (LPCTSTR)c.Print() );

      b--;
      wprintf( TEXT("%s\n"), (LPCTSTR)b.Print() );
   }

   {
      Rational a( contextualize< Integer as sX::Numerator >::Initialize( 2 ), 
                  contextualize< Integer as sX::Denominator >::Initialize( 3 ) );

      Rational b( contextualize< Integer as sX::Numerator >::Initialize( 3 ), 
                  contextualize< Integer as sX::Denominator >::Initialize( 4 ) );

      Rational c( contextualize< Integer as sX::Numerator >::Initialize( 7 ), 
                  contextualize< Integer as sX::Denominator >::Initialize( 2 ) );

      Rational d( -5 );

      Rational e = ((a + b ) * c) / (d - 456 * c);

      wprintf(TEXT("e=%s; e (as floating approximation) = %.16f\n"), (LPCTSTR)e.Print(), e.GetAsDouble());
   }
}