Convert -1 512 038 461 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -1 512 038 461(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-1 512 038 461 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:
|-1 512 038 461| = 1 512 038 461
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;
- 1 512 038 461 ÷ 2 = 756 019 230 + 1;
- 756 019 230 ÷ 2 = 378 009 615 + 0;
- 378 009 615 ÷ 2 = 189 004 807 + 1;
- 189 004 807 ÷ 2 = 94 502 403 + 1;
- 94 502 403 ÷ 2 = 47 251 201 + 1;
- 47 251 201 ÷ 2 = 23 625 600 + 1;
- 23 625 600 ÷ 2 = 11 812 800 + 0;
- 11 812 800 ÷ 2 = 5 906 400 + 0;
- 5 906 400 ÷ 2 = 2 953 200 + 0;
- 2 953 200 ÷ 2 = 1 476 600 + 0;
- 1 476 600 ÷ 2 = 738 300 + 0;
- 738 300 ÷ 2 = 369 150 + 0;
- 369 150 ÷ 2 = 184 575 + 0;
- 184 575 ÷ 2 = 92 287 + 1;
- 92 287 ÷ 2 = 46 143 + 1;
- 46 143 ÷ 2 = 23 071 + 1;
- 23 071 ÷ 2 = 11 535 + 1;
- 11 535 ÷ 2 = 5 767 + 1;
- 5 767 ÷ 2 = 2 883 + 1;
- 2 883 ÷ 2 = 1 441 + 1;
- 1 441 ÷ 2 = 720 + 1;
- 720 ÷ 2 = 360 + 0;
- 360 ÷ 2 = 180 + 0;
- 180 ÷ 2 = 90 + 0;
- 90 ÷ 2 = 45 + 0;
- 45 ÷ 2 = 22 + 1;
- 22 ÷ 2 = 11 + 0;
- 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.
1 512 038 461(10) = 101 1010 0001 1111 1110 0000 0011 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) 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, 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.
1 512 038 461(10) = 0101 1010 0001 1111 1110 0000 0011 1101
6. Get the negative integer number representation. Part 1:
- To write the negative integer number on 32 bits (4 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.
!(0101 1010 0001 1111 1110 0000 0011 1101)
= 1010 0101 1110 0000 0001 1111 1100 0010
7. Get the negative integer number representation. Part 2:
- To write the negative integer number on 32 bits (4 Bytes), as a signed binary in two's complement representation, add 1 to the number calculated above 1010 0101 1110 0000 0001 1111 1100 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):
-1 512 038 461 =
1010 0101 1110 0000 0001 1111 1100 0010 + 1
Decimal Number -1 512 038 461(10) converted to signed binary in two's complement representation:
-1 512 038 461(10) = 1010 0101 1110 0000 0001 1111 1100 0011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.