1. Divide the number repeatedly by 2:
Keep track of each remainder.
We stop when we get a quotient that is equal to zero.
- division = quotient + remainder;
- 51 605 842 ÷ 2 = 25 802 921 + 0;
- 25 802 921 ÷ 2 = 12 901 460 + 1;
- 12 901 460 ÷ 2 = 6 450 730 + 0;
- 6 450 730 ÷ 2 = 3 225 365 + 0;
- 3 225 365 ÷ 2 = 1 612 682 + 1;
- 1 612 682 ÷ 2 = 806 341 + 0;
- 806 341 ÷ 2 = 403 170 + 1;
- 403 170 ÷ 2 = 201 585 + 0;
- 201 585 ÷ 2 = 100 792 + 1;
- 100 792 ÷ 2 = 50 396 + 0;
- 50 396 ÷ 2 = 25 198 + 0;
- 25 198 ÷ 2 = 12 599 + 0;
- 12 599 ÷ 2 = 6 299 + 1;
- 6 299 ÷ 2 = 3 149 + 1;
- 3 149 ÷ 2 = 1 574 + 1;
- 1 574 ÷ 2 = 787 + 0;
- 787 ÷ 2 = 393 + 1;
- 393 ÷ 2 = 196 + 1;
- 196 ÷ 2 = 98 + 0;
- 98 ÷ 2 = 49 + 0;
- 49 ÷ 2 = 24 + 1;
- 24 ÷ 2 = 12 + 0;
- 12 ÷ 2 = 6 + 0;
- 6 ÷ 2 = 3 + 0;
- 3 ÷ 2 = 1 + 1;
- 1 ÷ 2 = 0 + 1;
2. Construct the base 2 representation of the positive number:
Take all the remainders starting from the bottom of the list constructed above.
51 605 842(10) = 11 0001 0011 0111 0001 0101 0010(2)
3. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 26.
- A signed binary's bit length must be equal to a power of 2, as of:
- 21 = 2; 22 = 4; 23 = 8; 24 = 16; 25 = 32; 26 = 64; ...
- The first bit (the leftmost) indicates the sign:
- 0 = positive integer number, 1 = negative integer number
The least number that is:
1) a power of 2
2) and is larger than the actual length, 26,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 32.
4. Get the positive binary computer representation on 32 bits (4 Bytes):
If needed, add extra 0s in front (to the left) of the base 2 number, up to the required length, 32.
Decimal Number 51 605 842(10) converted to signed binary in two's complement representation:
Spaces were used to group digits: for binary, by 4, for decimal, by 3.