What are the required steps to convert base 10 integer
number -4 128 930 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:
|-4 128 930| = 4 128 930
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;
- 4 128 930 ÷ 2 = 2 064 465 + 0;
- 2 064 465 ÷ 2 = 1 032 232 + 1;
- 1 032 232 ÷ 2 = 516 116 + 0;
- 516 116 ÷ 2 = 258 058 + 0;
- 258 058 ÷ 2 = 129 029 + 0;
- 129 029 ÷ 2 = 64 514 + 1;
- 64 514 ÷ 2 = 32 257 + 0;
- 32 257 ÷ 2 = 16 128 + 1;
- 16 128 ÷ 2 = 8 064 + 0;
- 8 064 ÷ 2 = 4 032 + 0;
- 4 032 ÷ 2 = 2 016 + 0;
- 2 016 ÷ 2 = 1 008 + 0;
- 1 008 ÷ 2 = 504 + 0;
- 504 ÷ 2 = 252 + 0;
- 252 ÷ 2 = 126 + 0;
- 126 ÷ 2 = 63 + 0;
- 63 ÷ 2 = 31 + 1;
- 31 ÷ 2 = 15 + 1;
- 15 ÷ 2 = 7 + 1;
- 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.
4 128 930(10) = 11 1111 0000 0000 1010 0010(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 22.
- 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, 22,
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:
4 128 930(10) = 0000 0000 0011 1111 0000 0000 1010 0010
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...
-4 128 930(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-4 128 930(10) = 1000 0000 0011 1111 0000 0000 1010 0010
Spaces were used to group digits: for binary, by 4, for decimal, by 3.