How are integers represented in computer memory?

Question

binary code

I understand that the computer understands the binary code, and this code can be represented in the form of direct (sign bit everything is there), reverse, additional code. The reverse and additional code help to replace the subtraction procedure with addition. I mean, for example, -10+ 5=-5 (1111 1011 well, I wrote it down in the complementary code). Question: why then do we need the reverse, if there is an additional one?
One more question: How does the computer know when to use direct, when reverse (if it uses it at all), and when additional code

Answer 1

teacher, load this nonsense
, no matter how the computer understands it - you won’t change anything,
learn and apply