What are the required steps to convert base 10 integer
number -1 977 290 583 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:
|-1 977 290 583| = 1 977 290 583
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;
- 1 977 290 583 ÷ 2 = 988 645 291 + 1;
- 988 645 291 ÷ 2 = 494 322 645 + 1;
- 494 322 645 ÷ 2 = 247 161 322 + 1;
- 247 161 322 ÷ 2 = 123 580 661 + 0;
- 123 580 661 ÷ 2 = 61 790 330 + 1;
- 61 790 330 ÷ 2 = 30 895 165 + 0;
- 30 895 165 ÷ 2 = 15 447 582 + 1;
- 15 447 582 ÷ 2 = 7 723 791 + 0;
- 7 723 791 ÷ 2 = 3 861 895 + 1;
- 3 861 895 ÷ 2 = 1 930 947 + 1;
- 1 930 947 ÷ 2 = 965 473 + 1;
- 965 473 ÷ 2 = 482 736 + 1;
- 482 736 ÷ 2 = 241 368 + 0;
- 241 368 ÷ 2 = 120 684 + 0;
- 120 684 ÷ 2 = 60 342 + 0;
- 60 342 ÷ 2 = 30 171 + 0;
- 30 171 ÷ 2 = 15 085 + 1;
- 15 085 ÷ 2 = 7 542 + 1;
- 7 542 ÷ 2 = 3 771 + 0;
- 3 771 ÷ 2 = 1 885 + 1;
- 1 885 ÷ 2 = 942 + 1;
- 942 ÷ 2 = 471 + 0;
- 471 ÷ 2 = 235 + 1;
- 235 ÷ 2 = 117 + 1;
- 117 ÷ 2 = 58 + 1;
- 58 ÷ 2 = 29 + 0;
- 29 ÷ 2 = 14 + 1;
- 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.
1 977 290 583(10) = 111 0101 1101 1011 0000 1111 0101 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:
1 977 290 583(10) = 0111 0101 1101 1011 0000 1111 0101 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...
-1 977 290 583(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 977 290 583(10) = 1111 0101 1101 1011 0000 1111 0101 0111
Spaces were used to group digits: for binary, by 4, for decimal, by 3.