Using a small and fast sieve of Eratosthenes up to your limit you can know all about types of the integer numbers.
Here this maximum limit may be 300 000 000 000 and more.
Using the GMP library working like normal arithmetic created by Paul Herman for their numerators and their denominators this code is able to perform the mathematically exact operations to rational numbers of any size.
The user can enter commands on the keyboard but he can also use a file of commands.
Coming from https://github.com/anthay/Lisp90 lisp90.cpp is a mini Lisp interpreter done by Anthony C. Hay. This new release can perform the Lisp instructions written in the code.txt file, with or without included comments, before the interactive phase.