Convert -2 745 343 723 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -2 745 343 723(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-2 745 343 723 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:
|-2 745 343 723| = 2 745 343 723
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;
- 2 745 343 723 ÷ 2 = 1 372 671 861 + 1;
- 1 372 671 861 ÷ 2 = 686 335 930 + 1;
- 686 335 930 ÷ 2 = 343 167 965 + 0;
- 343 167 965 ÷ 2 = 171 583 982 + 1;
- 171 583 982 ÷ 2 = 85 791 991 + 0;
- 85 791 991 ÷ 2 = 42 895 995 + 1;
- 42 895 995 ÷ 2 = 21 447 997 + 1;
- 21 447 997 ÷ 2 = 10 723 998 + 1;
- 10 723 998 ÷ 2 = 5 361 999 + 0;
- 5 361 999 ÷ 2 = 2 680 999 + 1;
- 2 680 999 ÷ 2 = 1 340 499 + 1;
- 1 340 499 ÷ 2 = 670 249 + 1;
- 670 249 ÷ 2 = 335 124 + 1;
- 335 124 ÷ 2 = 167 562 + 0;
- 167 562 ÷ 2 = 83 781 + 0;
- 83 781 ÷ 2 = 41 890 + 1;
- 41 890 ÷ 2 = 20 945 + 0;
- 20 945 ÷ 2 = 10 472 + 1;
- 10 472 ÷ 2 = 5 236 + 0;
- 5 236 ÷ 2 = 2 618 + 0;
- 2 618 ÷ 2 = 1 309 + 0;
- 1 309 ÷ 2 = 654 + 1;
- 654 ÷ 2 = 327 + 0;
- 327 ÷ 2 = 163 + 1;
- 163 ÷ 2 = 81 + 1;
- 81 ÷ 2 = 40 + 1;
- 40 ÷ 2 = 20 + 0;
- 20 ÷ 2 = 10 + 0;
- 10 ÷ 2 = 5 + 0;
- 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.
2 745 343 723(10) = 1010 0011 1010 0010 1001 1110 1110 1011(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 32.
- 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, 32,
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.
2 745 343 723(10) = 0000 0000 0000 0000 0000 0000 0000 0000 1010 0011 1010 0010 1001 1110 1110 1011
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 0000 1010 0011 1010 0010 1001 1110 1110 1011)
= 1111 1111 1111 1111 1111 1111 1111 1111 0101 1100 0101 1101 0110 0001 0001 0100
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 1111 0101 1100 0101 1101 0110 0001 0001 0100 (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):
-2 745 343 723 =
1111 1111 1111 1111 1111 1111 1111 1111 0101 1100 0101 1101 0110 0001 0001 0100 + 1
Decimal Number -2 745 343 723(10) converted to signed binary in two's complement representation:
-2 745 343 723(10) = 1111 1111 1111 1111 1111 1111 1111 1111 0101 1100 0101 1101 0110 0001 0001 0101
Spaces were used to group digits: for binary, by 4, for decimal, by 3.