What are the required steps to convert base 10 integer
number -1 705 045 975 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. Start with the positive version of the number:
|-1 705 045 975| = 1 705 045 975
2. 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;
- 1 705 045 975 ÷ 2 = 852 522 987 + 1;
- 852 522 987 ÷ 2 = 426 261 493 + 1;
- 426 261 493 ÷ 2 = 213 130 746 + 1;
- 213 130 746 ÷ 2 = 106 565 373 + 0;
- 106 565 373 ÷ 2 = 53 282 686 + 1;
- 53 282 686 ÷ 2 = 26 641 343 + 0;
- 26 641 343 ÷ 2 = 13 320 671 + 1;
- 13 320 671 ÷ 2 = 6 660 335 + 1;
- 6 660 335 ÷ 2 = 3 330 167 + 1;
- 3 330 167 ÷ 2 = 1 665 083 + 1;
- 1 665 083 ÷ 2 = 832 541 + 1;
- 832 541 ÷ 2 = 416 270 + 1;
- 416 270 ÷ 2 = 208 135 + 0;
- 208 135 ÷ 2 = 104 067 + 1;
- 104 067 ÷ 2 = 52 033 + 1;
- 52 033 ÷ 2 = 26 016 + 1;
- 26 016 ÷ 2 = 13 008 + 0;
- 13 008 ÷ 2 = 6 504 + 0;
- 6 504 ÷ 2 = 3 252 + 0;
- 3 252 ÷ 2 = 1 626 + 0;
- 1 626 ÷ 2 = 813 + 0;
- 813 ÷ 2 = 406 + 1;
- 406 ÷ 2 = 203 + 0;
- 203 ÷ 2 = 101 + 1;
- 101 ÷ 2 = 50 + 1;
- 50 ÷ 2 = 25 + 0;
- 25 ÷ 2 = 12 + 1;
- 12 ÷ 2 = 6 + 0;
- 6 ÷ 2 = 3 + 0;
- 3 ÷ 2 = 1 + 1;
- 1 ÷ 2 = 0 + 1;
3. Construct the base 2 representation of the positive number:
Take all the remainders starting from the bottom of the list constructed above.
1 705 045 975(10) = 110 0101 1010 0000 1110 1111 1101 0111(2)
4. 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.
5. 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:
1 705 045 975(10) = 0110 0101 1010 0000 1110 1111 1101 0111
6. Get the negative integer number representation:
To get the negative integer number representation on 32 bits (4 Bytes),
... change the first bit (the leftmost), from 0 to 1...
-1 705 045 975(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 705 045 975(10) = 1110 0101 1010 0000 1110 1111 1101 0111
Spaces were used to group digits: for binary, by 4, for decimal, by 3.