Convert -1 100 000 000 328 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -1 100 000 000 328(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-1 100 000 000 328 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:
|-1 100 000 000 328| = 1 100 000 000 328
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;
- 1 100 000 000 328 ÷ 2 = 550 000 000 164 + 0;
- 550 000 000 164 ÷ 2 = 275 000 000 082 + 0;
- 275 000 000 082 ÷ 2 = 137 500 000 041 + 0;
- 137 500 000 041 ÷ 2 = 68 750 000 020 + 1;
- 68 750 000 020 ÷ 2 = 34 375 000 010 + 0;
- 34 375 000 010 ÷ 2 = 17 187 500 005 + 0;
- 17 187 500 005 ÷ 2 = 8 593 750 002 + 1;
- 8 593 750 002 ÷ 2 = 4 296 875 001 + 0;
- 4 296 875 001 ÷ 2 = 2 148 437 500 + 1;
- 2 148 437 500 ÷ 2 = 1 074 218 750 + 0;
- 1 074 218 750 ÷ 2 = 537 109 375 + 0;
- 537 109 375 ÷ 2 = 268 554 687 + 1;
- 268 554 687 ÷ 2 = 134 277 343 + 1;
- 134 277 343 ÷ 2 = 67 138 671 + 1;
- 67 138 671 ÷ 2 = 33 569 335 + 1;
- 33 569 335 ÷ 2 = 16 784 667 + 1;
- 16 784 667 ÷ 2 = 8 392 333 + 1;
- 8 392 333 ÷ 2 = 4 196 166 + 1;
- 4 196 166 ÷ 2 = 2 098 083 + 0;
- 2 098 083 ÷ 2 = 1 049 041 + 1;
- 1 049 041 ÷ 2 = 524 520 + 1;
- 524 520 ÷ 2 = 262 260 + 0;
- 262 260 ÷ 2 = 131 130 + 0;
- 131 130 ÷ 2 = 65 565 + 0;
- 65 565 ÷ 2 = 32 782 + 1;
- 32 782 ÷ 2 = 16 391 + 0;
- 16 391 ÷ 2 = 8 195 + 1;
- 8 195 ÷ 2 = 4 097 + 1;
- 4 097 ÷ 2 = 2 048 + 1;
- 2 048 ÷ 2 = 1 024 + 0;
- 1 024 ÷ 2 = 512 + 0;
- 512 ÷ 2 = 256 + 0;
- 256 ÷ 2 = 128 + 0;
- 128 ÷ 2 = 64 + 0;
- 64 ÷ 2 = 32 + 0;
- 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.
1 100 000 000 328(10) = 1 0000 0000 0001 1101 0001 1011 1111 1001 0100 1000(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 41.
- 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, 41,
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.
1 100 000 000 328(10) = 0000 0000 0000 0000 0000 0001 0000 0000 0001 1101 0001 1011 1111 1001 0100 1000
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 0001 0000 0000 0001 1101 0001 1011 1111 1001 0100 1000)
= 1111 1111 1111 1111 1111 1110 1111 1111 1110 0010 1110 0100 0000 0110 1011 0111
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 1110 1111 1111 1110 0010 1110 0100 0000 0110 1011 0111 (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):
-1 100 000 000 328 =
1111 1111 1111 1111 1111 1110 1111 1111 1110 0010 1110 0100 0000 0110 1011 0111 + 1
Decimal Number -1 100 000 000 328(10) converted to signed binary in two's complement representation:
-1 100 000 000 328(10) = 1111 1111 1111 1111 1111 1110 1111 1111 1110 0010 1110 0100 0000 0110 1011 1000
Spaces were used to group digits: for binary, by 4, for decimal, by 3.