What are the required steps to convert base 10 integer
number -1 594 748 685 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:
|-1 594 748 685| = 1 594 748 685
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;
- 1 594 748 685 ÷ 2 = 797 374 342 + 1;
- 797 374 342 ÷ 2 = 398 687 171 + 0;
- 398 687 171 ÷ 2 = 199 343 585 + 1;
- 199 343 585 ÷ 2 = 99 671 792 + 1;
- 99 671 792 ÷ 2 = 49 835 896 + 0;
- 49 835 896 ÷ 2 = 24 917 948 + 0;
- 24 917 948 ÷ 2 = 12 458 974 + 0;
- 12 458 974 ÷ 2 = 6 229 487 + 0;
- 6 229 487 ÷ 2 = 3 114 743 + 1;
- 3 114 743 ÷ 2 = 1 557 371 + 1;
- 1 557 371 ÷ 2 = 778 685 + 1;
- 778 685 ÷ 2 = 389 342 + 1;
- 389 342 ÷ 2 = 194 671 + 0;
- 194 671 ÷ 2 = 97 335 + 1;
- 97 335 ÷ 2 = 48 667 + 1;
- 48 667 ÷ 2 = 24 333 + 1;
- 24 333 ÷ 2 = 12 166 + 1;
- 12 166 ÷ 2 = 6 083 + 0;
- 6 083 ÷ 2 = 3 041 + 1;
- 3 041 ÷ 2 = 1 520 + 1;
- 1 520 ÷ 2 = 760 + 0;
- 760 ÷ 2 = 380 + 0;
- 380 ÷ 2 = 190 + 0;
- 190 ÷ 2 = 95 + 0;
- 95 ÷ 2 = 47 + 1;
- 47 ÷ 2 = 23 + 1;
- 23 ÷ 2 = 11 + 1;
- 11 ÷ 2 = 5 + 1;
- 5 ÷ 2 = 2 + 1;
- 2 ÷ 2 = 1 + 0;
- 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.
1 594 748 685(10) = 101 1111 0000 1101 1110 1111 0000 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:
1 594 748 685(10) = 0101 1111 0000 1101 1110 1111 0000 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...
-1 594 748 685(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 594 748 685(10) = 1101 1111 0000 1101 1110 1111 0000 1101
Spaces were used to group digits: for binary, by 4, for decimal, by 3.