Convert -8 740 470 266 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -8 740 470 266(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-8 740 470 266 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:
|-8 740 470 266| = 8 740 470 266
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;
- 8 740 470 266 ÷ 2 = 4 370 235 133 + 0;
- 4 370 235 133 ÷ 2 = 2 185 117 566 + 1;
- 2 185 117 566 ÷ 2 = 1 092 558 783 + 0;
- 1 092 558 783 ÷ 2 = 546 279 391 + 1;
- 546 279 391 ÷ 2 = 273 139 695 + 1;
- 273 139 695 ÷ 2 = 136 569 847 + 1;
- 136 569 847 ÷ 2 = 68 284 923 + 1;
- 68 284 923 ÷ 2 = 34 142 461 + 1;
- 34 142 461 ÷ 2 = 17 071 230 + 1;
- 17 071 230 ÷ 2 = 8 535 615 + 0;
- 8 535 615 ÷ 2 = 4 267 807 + 1;
- 4 267 807 ÷ 2 = 2 133 903 + 1;
- 2 133 903 ÷ 2 = 1 066 951 + 1;
- 1 066 951 ÷ 2 = 533 475 + 1;
- 533 475 ÷ 2 = 266 737 + 1;
- 266 737 ÷ 2 = 133 368 + 1;
- 133 368 ÷ 2 = 66 684 + 0;
- 66 684 ÷ 2 = 33 342 + 0;
- 33 342 ÷ 2 = 16 671 + 0;
- 16 671 ÷ 2 = 8 335 + 1;
- 8 335 ÷ 2 = 4 167 + 1;
- 4 167 ÷ 2 = 2 083 + 1;
- 2 083 ÷ 2 = 1 041 + 1;
- 1 041 ÷ 2 = 520 + 1;
- 520 ÷ 2 = 260 + 0;
- 260 ÷ 2 = 130 + 0;
- 130 ÷ 2 = 65 + 0;
- 65 ÷ 2 = 32 + 1;
- 32 ÷ 2 = 16 + 0;
- 16 ÷ 2 = 8 + 0;
- 8 ÷ 2 = 4 + 0;
- 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.
8 740 470 266(10) = 10 0000 1000 1111 1000 1111 1101 1111 1010(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 34.
- 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, 34,
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.
8 740 470 266(10) = 0000 0000 0000 0000 0000 0000 0000 0010 0000 1000 1111 1000 1111 1101 1111 1010
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 0010 0000 1000 1111 1000 1111 1101 1111 1010)
= 1111 1111 1111 1111 1111 1111 1111 1101 1111 0111 0000 0111 0000 0010 0000 0101
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 1101 1111 0111 0000 0111 0000 0010 0000 0101 (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):
-8 740 470 266 =
1111 1111 1111 1111 1111 1111 1111 1101 1111 0111 0000 0111 0000 0010 0000 0101 + 1
Decimal Number -8 740 470 266(10) converted to signed binary in two's complement representation:
-8 740 470 266(10) = 1111 1111 1111 1111 1111 1111 1111 1101 1111 0111 0000 0111 0000 0010 0000 0110
Spaces were used to group digits: for binary, by 4, for decimal, by 3.