Challenge of the Month - April 2016 has been started. This month, calculation by hand is picked up as a community suggestions:

**Community Suggestions**

This month the community suggestions for challenges were posted in separate threads. Thanks for all suggestions.

Post answers here or on the challenge threads linked to below.

- Create a fully functional calculator (8-digit, basic calculator, not scientific) but do all the calculations by hand...meaning that if the user wants 356 * 8...the program should multiply 8*6 then 8*5+4 then 8*3+4. Just like you would do it if you had to multiply with pencil and paper. This would require addition, subtraction, multiplication and division and as an added challenge, negative numbers. By jherch77 (
**ORIGINAL POST**).

This thread by jherch77 is that I wrote once in this blog. Last time I wrote that I love this challenge. Today, I'd like to write why I love the calculation by hand so much.

I wrote an addition program RHP722.

So many people know how to add by hand like this program. I think how to add by hand is the most popular algorithm. That is the reason why I love this challenge.

Let's start programming well known algorithms! You may be noticed the difference between human and computer by trying this challenge.

Thank you litdev for picking up jherch77's challenge.

nice work nonky))

i added binary addition to ur prg: VTK605

now some animations added and binary & hex addition too: RWG461

Nice challenge!

Tryhest, nice binary and hexadecimal program!