Convert -64 424 509 507 to a Signed Binary in Two's (2's) Complement Representation
How to convert decimal number -64 424 509 507(10) to a signed binary in two's (2's) complement representation
What are the steps to convert decimal number
-64 424 509 507 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:
|-64 424 509 507| = 64 424 509 507
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;
- 64 424 509 507 ÷ 2 = 32 212 254 753 + 1;
- 32 212 254 753 ÷ 2 = 16 106 127 376 + 1;
- 16 106 127 376 ÷ 2 = 8 053 063 688 + 0;
- 8 053 063 688 ÷ 2 = 4 026 531 844 + 0;
- 4 026 531 844 ÷ 2 = 2 013 265 922 + 0;
- 2 013 265 922 ÷ 2 = 1 006 632 961 + 0;
- 1 006 632 961 ÷ 2 = 503 316 480 + 1;
- 503 316 480 ÷ 2 = 251 658 240 + 0;
- 251 658 240 ÷ 2 = 125 829 120 + 0;
- 125 829 120 ÷ 2 = 62 914 560 + 0;
- 62 914 560 ÷ 2 = 31 457 280 + 0;
- 31 457 280 ÷ 2 = 15 728 640 + 0;
- 15 728 640 ÷ 2 = 7 864 320 + 0;
- 7 864 320 ÷ 2 = 3 932 160 + 0;
- 3 932 160 ÷ 2 = 1 966 080 + 0;
- 1 966 080 ÷ 2 = 983 040 + 0;
- 983 040 ÷ 2 = 491 520 + 0;
- 491 520 ÷ 2 = 245 760 + 0;
- 245 760 ÷ 2 = 122 880 + 0;
- 122 880 ÷ 2 = 61 440 + 0;
- 61 440 ÷ 2 = 30 720 + 0;
- 30 720 ÷ 2 = 15 360 + 0;
- 15 360 ÷ 2 = 7 680 + 0;
- 7 680 ÷ 2 = 3 840 + 0;
- 3 840 ÷ 2 = 1 920 + 0;
- 1 920 ÷ 2 = 960 + 0;
- 960 ÷ 2 = 480 + 0;
- 480 ÷ 2 = 240 + 0;
- 240 ÷ 2 = 120 + 0;
- 120 ÷ 2 = 60 + 0;
- 60 ÷ 2 = 30 + 0;
- 30 ÷ 2 = 15 + 0;
- 15 ÷ 2 = 7 + 1;
- 7 ÷ 2 = 3 + 1;
- 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.
64 424 509 507(10) = 1111 0000 0000 0000 0000 0000 0000 0100 0011(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 36.
- 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, 36,
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.
64 424 509 507(10) = 0000 0000 0000 0000 0000 0000 0000 1111 0000 0000 0000 0000 0000 0000 0100 0011
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 1111 0000 0000 0000 0000 0000 0000 0100 0011)
= 1111 1111 1111 1111 1111 1111 1111 0000 1111 1111 1111 1111 1111 1111 1011 1100
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 0000 1111 1111 1111 1111 1111 1111 1011 1100 (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):
-64 424 509 507 =
1111 1111 1111 1111 1111 1111 1111 0000 1111 1111 1111 1111 1111 1111 1011 1100 + 1
Decimal Number -64 424 509 507(10) converted to signed binary in two's complement representation:
-64 424 509 507(10) = 1111 1111 1111 1111 1111 1111 1111 0000 1111 1111 1111 1111 1111 1111 1011 1101
Spaces were used to group digits: for binary, by 4, for decimal, by 3.