What are the required steps to convert base 10 integer
number -2 080 987 304 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:
|-2 080 987 304| = 2 080 987 304
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;
- 2 080 987 304 ÷ 2 = 1 040 493 652 + 0;
- 1 040 493 652 ÷ 2 = 520 246 826 + 0;
- 520 246 826 ÷ 2 = 260 123 413 + 0;
- 260 123 413 ÷ 2 = 130 061 706 + 1;
- 130 061 706 ÷ 2 = 65 030 853 + 0;
- 65 030 853 ÷ 2 = 32 515 426 + 1;
- 32 515 426 ÷ 2 = 16 257 713 + 0;
- 16 257 713 ÷ 2 = 8 128 856 + 1;
- 8 128 856 ÷ 2 = 4 064 428 + 0;
- 4 064 428 ÷ 2 = 2 032 214 + 0;
- 2 032 214 ÷ 2 = 1 016 107 + 0;
- 1 016 107 ÷ 2 = 508 053 + 1;
- 508 053 ÷ 2 = 254 026 + 1;
- 254 026 ÷ 2 = 127 013 + 0;
- 127 013 ÷ 2 = 63 506 + 1;
- 63 506 ÷ 2 = 31 753 + 0;
- 31 753 ÷ 2 = 15 876 + 1;
- 15 876 ÷ 2 = 7 938 + 0;
- 7 938 ÷ 2 = 3 969 + 0;
- 3 969 ÷ 2 = 1 984 + 1;
- 1 984 ÷ 2 = 992 + 0;
- 992 ÷ 2 = 496 + 0;
- 496 ÷ 2 = 248 + 0;
- 248 ÷ 2 = 124 + 0;
- 124 ÷ 2 = 62 + 0;
- 62 ÷ 2 = 31 + 0;
- 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.
2 080 987 304(10) = 111 1100 0000 1001 0101 1000 1010 1000(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:
2 080 987 304(10) = 0111 1100 0000 1001 0101 1000 1010 1000
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...
-2 080 987 304(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-2 080 987 304(10) = 1111 1100 0000 1001 0101 1000 1010 1000
Spaces were used to group digits: for binary, by 4, for decimal, by 3.