A simple Calculator

Greetings,

Forgive me if this is in the wrong place.

I am looking for a calculator schematic that is made of logic gates.

I am playing a game called minecraft with the tekkit and redpower 2 mods.
Inside this game they have all the basic logic gates to make this calculator...however i am unable to locate the schematics to make this work. I have been looking on the web for 3 or 4 weeks and have become irritated at looking. So i decided to ask the crazy engineers in hopes that i might find someone here who knows where i can find one.

Thank you in advance for your advice

SeaEagle