What are the required steps to convert base 10 integer
number -1 299 935 299 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:
|-1 299 935 299| = 1 299 935 299
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;
- 1 299 935 299 ÷ 2 = 649 967 649 + 1;
- 649 967 649 ÷ 2 = 324 983 824 + 1;
- 324 983 824 ÷ 2 = 162 491 912 + 0;
- 162 491 912 ÷ 2 = 81 245 956 + 0;
- 81 245 956 ÷ 2 = 40 622 978 + 0;
- 40 622 978 ÷ 2 = 20 311 489 + 0;
- 20 311 489 ÷ 2 = 10 155 744 + 1;
- 10 155 744 ÷ 2 = 5 077 872 + 0;
- 5 077 872 ÷ 2 = 2 538 936 + 0;
- 2 538 936 ÷ 2 = 1 269 468 + 0;
- 1 269 468 ÷ 2 = 634 734 + 0;
- 634 734 ÷ 2 = 317 367 + 0;
- 317 367 ÷ 2 = 158 683 + 1;
- 158 683 ÷ 2 = 79 341 + 1;
- 79 341 ÷ 2 = 39 670 + 1;
- 39 670 ÷ 2 = 19 835 + 0;
- 19 835 ÷ 2 = 9 917 + 1;
- 9 917 ÷ 2 = 4 958 + 1;
- 4 958 ÷ 2 = 2 479 + 0;
- 2 479 ÷ 2 = 1 239 + 1;
- 1 239 ÷ 2 = 619 + 1;
- 619 ÷ 2 = 309 + 1;
- 309 ÷ 2 = 154 + 1;
- 154 ÷ 2 = 77 + 0;
- 77 ÷ 2 = 38 + 1;
- 38 ÷ 2 = 19 + 0;
- 19 ÷ 2 = 9 + 1;
- 9 ÷ 2 = 4 + 1;
- 4 ÷ 2 = 2 + 0;
- 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.
1 299 935 299(10) = 100 1101 0111 1011 0111 0000 0100 0011(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:
1 299 935 299(10) = 0100 1101 0111 1011 0111 0000 0100 0011
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...
-1 299 935 299(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 299 935 299(10) = 1100 1101 0111 1011 0111 0000 0100 0011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.