What are the required steps to convert base 10 integer
number -1 816 865 613 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:
|-1 816 865 613| = 1 816 865 613
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;
- 1 816 865 613 ÷ 2 = 908 432 806 + 1;
- 908 432 806 ÷ 2 = 454 216 403 + 0;
- 454 216 403 ÷ 2 = 227 108 201 + 1;
- 227 108 201 ÷ 2 = 113 554 100 + 1;
- 113 554 100 ÷ 2 = 56 777 050 + 0;
- 56 777 050 ÷ 2 = 28 388 525 + 0;
- 28 388 525 ÷ 2 = 14 194 262 + 1;
- 14 194 262 ÷ 2 = 7 097 131 + 0;
- 7 097 131 ÷ 2 = 3 548 565 + 1;
- 3 548 565 ÷ 2 = 1 774 282 + 1;
- 1 774 282 ÷ 2 = 887 141 + 0;
- 887 141 ÷ 2 = 443 570 + 1;
- 443 570 ÷ 2 = 221 785 + 0;
- 221 785 ÷ 2 = 110 892 + 1;
- 110 892 ÷ 2 = 55 446 + 0;
- 55 446 ÷ 2 = 27 723 + 0;
- 27 723 ÷ 2 = 13 861 + 1;
- 13 861 ÷ 2 = 6 930 + 1;
- 6 930 ÷ 2 = 3 465 + 0;
- 3 465 ÷ 2 = 1 732 + 1;
- 1 732 ÷ 2 = 866 + 0;
- 866 ÷ 2 = 433 + 0;
- 433 ÷ 2 = 216 + 1;
- 216 ÷ 2 = 108 + 0;
- 108 ÷ 2 = 54 + 0;
- 54 ÷ 2 = 27 + 0;
- 27 ÷ 2 = 13 + 1;
- 13 ÷ 2 = 6 + 1;
- 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.
1 816 865 613(10) = 110 1100 0100 1011 0010 1011 0100 1101(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:
1 816 865 613(10) = 0110 1100 0100 1011 0010 1011 0100 1101
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...
-1 816 865 613(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 816 865 613(10) = 1110 1100 0100 1011 0010 1011 0100 1101
Spaces were used to group digits: for binary, by 4, for decimal, by 3.