What are the required steps to convert base 10 integer
number -1 938 485 383 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:
|-1 938 485 383| = 1 938 485 383
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;
- 1 938 485 383 ÷ 2 = 969 242 691 + 1;
- 969 242 691 ÷ 2 = 484 621 345 + 1;
- 484 621 345 ÷ 2 = 242 310 672 + 1;
- 242 310 672 ÷ 2 = 121 155 336 + 0;
- 121 155 336 ÷ 2 = 60 577 668 + 0;
- 60 577 668 ÷ 2 = 30 288 834 + 0;
- 30 288 834 ÷ 2 = 15 144 417 + 0;
- 15 144 417 ÷ 2 = 7 572 208 + 1;
- 7 572 208 ÷ 2 = 3 786 104 + 0;
- 3 786 104 ÷ 2 = 1 893 052 + 0;
- 1 893 052 ÷ 2 = 946 526 + 0;
- 946 526 ÷ 2 = 473 263 + 0;
- 473 263 ÷ 2 = 236 631 + 1;
- 236 631 ÷ 2 = 118 315 + 1;
- 118 315 ÷ 2 = 59 157 + 1;
- 59 157 ÷ 2 = 29 578 + 1;
- 29 578 ÷ 2 = 14 789 + 0;
- 14 789 ÷ 2 = 7 394 + 1;
- 7 394 ÷ 2 = 3 697 + 0;
- 3 697 ÷ 2 = 1 848 + 1;
- 1 848 ÷ 2 = 924 + 0;
- 924 ÷ 2 = 462 + 0;
- 462 ÷ 2 = 231 + 0;
- 231 ÷ 2 = 115 + 1;
- 115 ÷ 2 = 57 + 1;
- 57 ÷ 2 = 28 + 1;
- 28 ÷ 2 = 14 + 0;
- 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.
1 938 485 383(10) = 111 0011 1000 1010 1111 0000 1000 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:
1 938 485 383(10) = 0111 0011 1000 1010 1111 0000 1000 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...
-1 938 485 383(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 938 485 383(10) = 1111 0011 1000 1010 1111 0000 1000 0111
Spaces were used to group digits: for binary, by 4, for decimal, by 3.