What are the required steps to convert base 10 integer
number 17 111 999 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. 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;
- 17 111 999 ÷ 2 = 8 555 999 + 1;
- 8 555 999 ÷ 2 = 4 277 999 + 1;
- 4 277 999 ÷ 2 = 2 138 999 + 1;
- 2 138 999 ÷ 2 = 1 069 499 + 1;
- 1 069 499 ÷ 2 = 534 749 + 1;
- 534 749 ÷ 2 = 267 374 + 1;
- 267 374 ÷ 2 = 133 687 + 0;
- 133 687 ÷ 2 = 66 843 + 1;
- 66 843 ÷ 2 = 33 421 + 1;
- 33 421 ÷ 2 = 16 710 + 1;
- 16 710 ÷ 2 = 8 355 + 0;
- 8 355 ÷ 2 = 4 177 + 1;
- 4 177 ÷ 2 = 2 088 + 1;
- 2 088 ÷ 2 = 1 044 + 0;
- 1 044 ÷ 2 = 522 + 0;
- 522 ÷ 2 = 261 + 0;
- 261 ÷ 2 = 130 + 1;
- 130 ÷ 2 = 65 + 0;
- 65 ÷ 2 = 32 + 1;
- 32 ÷ 2 = 16 + 0;
- 16 ÷ 2 = 8 + 0;
- 8 ÷ 2 = 4 + 0;
- 4 ÷ 2 = 2 + 0;
- 2 ÷ 2 = 1 + 0;
- 1 ÷ 2 = 0 + 1;
2. Construct the base 2 representation of the positive number:
Take all the remainders starting from the bottom of the list constructed above.
17 111 999(10) = 1 0000 0101 0001 1011 1011 1111(2)
3. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 25.
- 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, 25,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 32.
4. 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:
17 111 999(10) Base 10 integer number converted and written as a signed binary code (in base 2):
17 111 999(10) = 0000 0001 0000 0101 0001 1011 1011 1111
Spaces were used to group digits: for binary, by 4, for decimal, by 3.