First of all, the first digit represents positive and negative values, 0 represents positive numbers, and 1 represents negative numbers.

Another concept is that a negative number equals a negative number (complement+1).

For example, if there are four people.

100 1 complement 01kloc-0/0 = 6

6+ 1 = 7 so 100 1 =-7.

In the same way; In a similar way

1000' s complement 011= 7

7+ 1 = 8, so 1000 =-8.

Complement of 1000000000000 01111111.

So100000000000 =-215.