What are the required steps to convert base 10 integer
number 1 485 798 779 to signed binary code (in base 2)?
- A signed integer, written in base ten, or a decimal system number, is a number written using the digits 0 through 9 and the sign, which can be positive (+) or negative (-). If positive, the sign is usually not written. A number written in base two, or binary, is a number written using only the digits 0 and 1.
1. Divide the number repeatedly by 2:
Keep track of each remainder.
Stop when you get a quotient that is equal to zero.
- division = quotient + remainder;
- 1 485 798 779 ÷ 2 = 742 899 389 + 1;
- 742 899 389 ÷ 2 = 371 449 694 + 1;
- 371 449 694 ÷ 2 = 185 724 847 + 0;
- 185 724 847 ÷ 2 = 92 862 423 + 1;
- 92 862 423 ÷ 2 = 46 431 211 + 1;
- 46 431 211 ÷ 2 = 23 215 605 + 1;
- 23 215 605 ÷ 2 = 11 607 802 + 1;
- 11 607 802 ÷ 2 = 5 803 901 + 0;
- 5 803 901 ÷ 2 = 2 901 950 + 1;
- 2 901 950 ÷ 2 = 1 450 975 + 0;
- 1 450 975 ÷ 2 = 725 487 + 1;
- 725 487 ÷ 2 = 362 743 + 1;
- 362 743 ÷ 2 = 181 371 + 1;
- 181 371 ÷ 2 = 90 685 + 1;
- 90 685 ÷ 2 = 45 342 + 1;
- 45 342 ÷ 2 = 22 671 + 0;
- 22 671 ÷ 2 = 11 335 + 1;
- 11 335 ÷ 2 = 5 667 + 1;
- 5 667 ÷ 2 = 2 833 + 1;
- 2 833 ÷ 2 = 1 416 + 1;
- 1 416 ÷ 2 = 708 + 0;
- 708 ÷ 2 = 354 + 0;
- 354 ÷ 2 = 177 + 0;
- 177 ÷ 2 = 88 + 1;
- 88 ÷ 2 = 44 + 0;
- 44 ÷ 2 = 22 + 0;
- 22 ÷ 2 = 11 + 0;
- 11 ÷ 2 = 5 + 1;
- 5 ÷ 2 = 2 + 1;
- 2 ÷ 2 = 1 + 0;
- 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.
1 485 798 779(10) = 101 1000 1000 1111 0111 1101 0111 1011(2)
3. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 31.
- 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) is reserved for 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, 31,
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:
1 485 798 779(10) Base 10 integer number converted and written as a signed binary code (in base 2):
1 485 798 779(10) = 0101 1000 1000 1111 0111 1101 0111 1011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.