Convert -431 291 956 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -431 291 956(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-431 291 956 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:
|-431 291 956| = 431 291 956
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;
- 431 291 956 ÷ 2 = 215 645 978 + 0;
- 215 645 978 ÷ 2 = 107 822 989 + 0;
- 107 822 989 ÷ 2 = 53 911 494 + 1;
- 53 911 494 ÷ 2 = 26 955 747 + 0;
- 26 955 747 ÷ 2 = 13 477 873 + 1;
- 13 477 873 ÷ 2 = 6 738 936 + 1;
- 6 738 936 ÷ 2 = 3 369 468 + 0;
- 3 369 468 ÷ 2 = 1 684 734 + 0;
- 1 684 734 ÷ 2 = 842 367 + 0;
- 842 367 ÷ 2 = 421 183 + 1;
- 421 183 ÷ 2 = 210 591 + 1;
- 210 591 ÷ 2 = 105 295 + 1;
- 105 295 ÷ 2 = 52 647 + 1;
- 52 647 ÷ 2 = 26 323 + 1;
- 26 323 ÷ 2 = 13 161 + 1;
- 13 161 ÷ 2 = 6 580 + 1;
- 6 580 ÷ 2 = 3 290 + 0;
- 3 290 ÷ 2 = 1 645 + 0;
- 1 645 ÷ 2 = 822 + 1;
- 822 ÷ 2 = 411 + 0;
- 411 ÷ 2 = 205 + 1;
- 205 ÷ 2 = 102 + 1;
- 102 ÷ 2 = 51 + 0;
- 51 ÷ 2 = 25 + 1;
- 25 ÷ 2 = 12 + 1;
- 12 ÷ 2 = 6 + 0;
- 6 ÷ 2 = 3 + 0;
- 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.
431 291 956(10) = 1 1001 1011 0100 1111 1110 0011 0100(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 29.
- 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, 29,
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.
431 291 956(10) = 0001 1001 1011 0100 1111 1110 0011 0100
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.
!(0001 1001 1011 0100 1111 1110 0011 0100)
= 1110 0110 0100 1011 0000 0001 1100 1011
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 1110 0110 0100 1011 0000 0001 1100 1011 (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):
-431 291 956 =
1110 0110 0100 1011 0000 0001 1100 1011 + 1
Decimal Number -431 291 956(10) converted to signed binary in two's complement representation:
-431 291 956(10) = 1110 0110 0100 1011 0000 0001 1100 1100
Spaces were used to group digits: for binary, by 4, for decimal, by 3.