It's a MCBE machine created by Lucas Bazán, a Brasilian minecraft player and youtuber: [url=/account/manage/projects/item/new/youtube.com/c/LucasBazán]youtube.com/c/LucasBazán[/url]
Was created in 1.19.0
It uses binary to make adittion and subtraction operations.

How to use/Rules:

1-Enter the first desired number.
2-Change the lever indicating which number is being saved.
3-Enter the second desired number.
4-Select the operation: addition (+) or subtraction (-)
5- Click on result (=) to calculate.

-Enter numbers up to 999. (less than 1000)
-Type slowly, wait for the last button pressed to release to press another.
-If a number reaches 3 places, when typing again aloud the next number will be saved as the second value.
-It is possible to switch between addition (+) and subtraction (-) at any time (no need to click on "=").
-Do not type while calculating.

2 Parts of the machine was created by mattbatwings. Thanks for the tutorials.