Convert -19 531 236 285 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -19 531 236 285(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-19 531 236 285 to a signed binary in two's (2's) complement representation?
- 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:
|-19 531 236 285| = 19 531 236 285
2. Divide the number repeatedly by 2:
Keep track of each remainder.
We stop when we get a quotient that is equal to zero.
- division = quotient + remainder;
- 19 531 236 285 ÷ 2 = 9 765 618 142 + 1;
- 9 765 618 142 ÷ 2 = 4 882 809 071 + 0;
- 4 882 809 071 ÷ 2 = 2 441 404 535 + 1;
- 2 441 404 535 ÷ 2 = 1 220 702 267 + 1;
- 1 220 702 267 ÷ 2 = 610 351 133 + 1;
- 610 351 133 ÷ 2 = 305 175 566 + 1;
- 305 175 566 ÷ 2 = 152 587 783 + 0;
- 152 587 783 ÷ 2 = 76 293 891 + 1;
- 76 293 891 ÷ 2 = 38 146 945 + 1;
- 38 146 945 ÷ 2 = 19 073 472 + 1;
- 19 073 472 ÷ 2 = 9 536 736 + 0;
- 9 536 736 ÷ 2 = 4 768 368 + 0;
- 4 768 368 ÷ 2 = 2 384 184 + 0;
- 2 384 184 ÷ 2 = 1 192 092 + 0;
- 1 192 092 ÷ 2 = 596 046 + 0;
- 596 046 ÷ 2 = 298 023 + 0;
- 298 023 ÷ 2 = 149 011 + 1;
- 149 011 ÷ 2 = 74 505 + 1;
- 74 505 ÷ 2 = 37 252 + 1;
- 37 252 ÷ 2 = 18 626 + 0;
- 18 626 ÷ 2 = 9 313 + 0;
- 9 313 ÷ 2 = 4 656 + 1;
- 4 656 ÷ 2 = 2 328 + 0;
- 2 328 ÷ 2 = 1 164 + 0;
- 1 164 ÷ 2 = 582 + 0;
- 582 ÷ 2 = 291 + 0;
- 291 ÷ 2 = 145 + 1;
- 145 ÷ 2 = 72 + 1;
- 72 ÷ 2 = 36 + 0;
- 36 ÷ 2 = 18 + 0;
- 18 ÷ 2 = 9 + 0;
- 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.
19 531 236 285(10) = 100 1000 1100 0010 0111 0000 0011 1011 1101(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 35.
- 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) indicates 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, 35,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 64.
5. Get the positive binary computer representation on 64 bits (8 Bytes):
If needed, add extra 0s in front (to the left) of the base 2 number, up to the required length, 64.
19 531 236 285(10) = 0000 0000 0000 0000 0000 0000 0000 0100 1000 1100 0010 0111 0000 0011 1011 1101
6. Get the negative integer number representation. Part 1:
- To write the negative integer number on 64 bits (8 Bytes), as a signed binary in one's complement representation, replace all the bits on 0 with 1s and all the bits set on 1 with 0s.
Reverse the digits, flip the digits:
Replace the bits set on 0 with 1s and the bits set on 1 with 0s.
!(0000 0000 0000 0000 0000 0000 0000 0100 1000 1100 0010 0111 0000 0011 1011 1101)
= 1111 1111 1111 1111 1111 1111 1111 1011 0111 0011 1101 1000 1111 1100 0100 0010
7. Get the negative integer number representation. Part 2:
- To write the negative integer number on 64 bits (8 Bytes), as a signed binary in two's complement representation, add 1 to the number calculated above 1111 1111 1111 1111 1111 1111 1111 1011 0111 0011 1101 1000 1111 1100 0100 0010 (to the signed binary in one's complement representation).
Binary addition carries on a value of 2:
- 0 + 0 = 0
- 0 + 1 = 1
- 1 + 1 = 10
- 1 + 10 = 11
- 1 + 11 = 100
Add 1 to the number calculated above
(to the signed binary number in one's complement representation):
-19 531 236 285 =
1111 1111 1111 1111 1111 1111 1111 1011 0111 0011 1101 1000 1111 1100 0100 0010 + 1
Decimal Number -19 531 236 285(10) converted to signed binary in two's complement representation:
-19 531 236 285(10) = 1111 1111 1111 1111 1111 1111 1111 1011 0111 0011 1101 1000 1111 1100 0100 0011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.