What are the required steps to convert base 10 integer
number -233 475 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:
|-233 475| = 233 475
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;
- 233 475 ÷ 2 = 116 737 + 1;
- 116 737 ÷ 2 = 58 368 + 1;
- 58 368 ÷ 2 = 29 184 + 0;
- 29 184 ÷ 2 = 14 592 + 0;
- 14 592 ÷ 2 = 7 296 + 0;
- 7 296 ÷ 2 = 3 648 + 0;
- 3 648 ÷ 2 = 1 824 + 0;
- 1 824 ÷ 2 = 912 + 0;
- 912 ÷ 2 = 456 + 0;
- 456 ÷ 2 = 228 + 0;
- 228 ÷ 2 = 114 + 0;
- 114 ÷ 2 = 57 + 0;
- 57 ÷ 2 = 28 + 1;
- 28 ÷ 2 = 14 + 0;
- 14 ÷ 2 = 7 + 0;
- 7 ÷ 2 = 3 + 1;
- 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.
233 475(10) = 11 1001 0000 0000 0011(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 18.
- 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, 18,
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:
233 475(10) = 0000 0000 0000 0011 1001 0000 0000 0011
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...
-233 475(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-233 475(10) = 1000 0000 0000 0011 1001 0000 0000 0011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.