Convert -368 934 881 430 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -368 934 881 430(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-368 934 881 430 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:
|-368 934 881 430| = 368 934 881 430
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;
- 368 934 881 430 ÷ 2 = 184 467 440 715 + 0;
- 184 467 440 715 ÷ 2 = 92 233 720 357 + 1;
- 92 233 720 357 ÷ 2 = 46 116 860 178 + 1;
- 46 116 860 178 ÷ 2 = 23 058 430 089 + 0;
- 23 058 430 089 ÷ 2 = 11 529 215 044 + 1;
- 11 529 215 044 ÷ 2 = 5 764 607 522 + 0;
- 5 764 607 522 ÷ 2 = 2 882 303 761 + 0;
- 2 882 303 761 ÷ 2 = 1 441 151 880 + 1;
- 1 441 151 880 ÷ 2 = 720 575 940 + 0;
- 720 575 940 ÷ 2 = 360 287 970 + 0;
- 360 287 970 ÷ 2 = 180 143 985 + 0;
- 180 143 985 ÷ 2 = 90 071 992 + 1;
- 90 071 992 ÷ 2 = 45 035 996 + 0;
- 45 035 996 ÷ 2 = 22 517 998 + 0;
- 22 517 998 ÷ 2 = 11 258 999 + 0;
- 11 258 999 ÷ 2 = 5 629 499 + 1;
- 5 629 499 ÷ 2 = 2 814 749 + 1;
- 2 814 749 ÷ 2 = 1 407 374 + 1;
- 1 407 374 ÷ 2 = 703 687 + 0;
- 703 687 ÷ 2 = 351 843 + 1;
- 351 843 ÷ 2 = 175 921 + 1;
- 175 921 ÷ 2 = 87 960 + 1;
- 87 960 ÷ 2 = 43 980 + 0;
- 43 980 ÷ 2 = 21 990 + 0;
- 21 990 ÷ 2 = 10 995 + 0;
- 10 995 ÷ 2 = 5 497 + 1;
- 5 497 ÷ 2 = 2 748 + 1;
- 2 748 ÷ 2 = 1 374 + 0;
- 1 374 ÷ 2 = 687 + 0;
- 687 ÷ 2 = 343 + 1;
- 343 ÷ 2 = 171 + 1;
- 171 ÷ 2 = 85 + 1;
- 85 ÷ 2 = 42 + 1;
- 42 ÷ 2 = 21 + 0;
- 21 ÷ 2 = 10 + 1;
- 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.
368 934 881 430(10) = 101 0101 1110 0110 0011 1011 1000 1000 1001 0110(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 39.
- 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, 39,
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.
368 934 881 430(10) = 0000 0000 0000 0000 0000 0000 0101 0101 1110 0110 0011 1011 1000 1000 1001 0110
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 0101 0101 1110 0110 0011 1011 1000 1000 1001 0110)
= 1111 1111 1111 1111 1111 1111 1010 1010 0001 1001 1100 0100 0111 0111 0110 1001
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 1010 1010 0001 1001 1100 0100 0111 0111 0110 1001 (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):
-368 934 881 430 =
1111 1111 1111 1111 1111 1111 1010 1010 0001 1001 1100 0100 0111 0111 0110 1001 + 1
Decimal Number -368 934 881 430(10) converted to signed binary in two's complement representation:
-368 934 881 430(10) = 1111 1111 1111 1111 1111 1111 1010 1010 0001 1001 1100 0100 0111 0111 0110 1010
Spaces were used to group digits: for binary, by 4, for decimal, by 3.