Convert -56 237 989 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -56 237 989(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-56 237 989 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:
|-56 237 989| = 56 237 989
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;
- 56 237 989 ÷ 2 = 28 118 994 + 1;
- 28 118 994 ÷ 2 = 14 059 497 + 0;
- 14 059 497 ÷ 2 = 7 029 748 + 1;
- 7 029 748 ÷ 2 = 3 514 874 + 0;
- 3 514 874 ÷ 2 = 1 757 437 + 0;
- 1 757 437 ÷ 2 = 878 718 + 1;
- 878 718 ÷ 2 = 439 359 + 0;
- 439 359 ÷ 2 = 219 679 + 1;
- 219 679 ÷ 2 = 109 839 + 1;
- 109 839 ÷ 2 = 54 919 + 1;
- 54 919 ÷ 2 = 27 459 + 1;
- 27 459 ÷ 2 = 13 729 + 1;
- 13 729 ÷ 2 = 6 864 + 1;
- 6 864 ÷ 2 = 3 432 + 0;
- 3 432 ÷ 2 = 1 716 + 0;
- 1 716 ÷ 2 = 858 + 0;
- 858 ÷ 2 = 429 + 0;
- 429 ÷ 2 = 214 + 1;
- 214 ÷ 2 = 107 + 0;
- 107 ÷ 2 = 53 + 1;
- 53 ÷ 2 = 26 + 1;
- 26 ÷ 2 = 13 + 0;
- 13 ÷ 2 = 6 + 1;
- 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.
56 237 989(10) = 11 0101 1010 0001 1111 1010 0101(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 26.
- 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, 26,
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.
56 237 989(10) = 0000 0011 0101 1010 0001 1111 1010 0101
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.
!(0000 0011 0101 1010 0001 1111 1010 0101)
= 1111 1100 1010 0101 1110 0000 0101 1010
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 1111 1100 1010 0101 1110 0000 0101 1010 (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):
-56 237 989 =
1111 1100 1010 0101 1110 0000 0101 1010 + 1
Decimal Number -56 237 989(10) converted to signed binary in two's complement representation:
-56 237 989(10) = 1111 1100 1010 0101 1110 0000 0101 1011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.