What are the required steps to convert base 10 integer
number -587 345 680 to signed binary code (in base 2)?
- 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:
|-587 345 680| = 587 345 680
2. Divide the number repeatedly by 2:
Keep track of each remainder.
Stop when you get a quotient that is equal to zero.
- division = quotient + remainder;
- 587 345 680 ÷ 2 = 293 672 840 + 0;
- 293 672 840 ÷ 2 = 146 836 420 + 0;
- 146 836 420 ÷ 2 = 73 418 210 + 0;
- 73 418 210 ÷ 2 = 36 709 105 + 0;
- 36 709 105 ÷ 2 = 18 354 552 + 1;
- 18 354 552 ÷ 2 = 9 177 276 + 0;
- 9 177 276 ÷ 2 = 4 588 638 + 0;
- 4 588 638 ÷ 2 = 2 294 319 + 0;
- 2 294 319 ÷ 2 = 1 147 159 + 1;
- 1 147 159 ÷ 2 = 573 579 + 1;
- 573 579 ÷ 2 = 286 789 + 1;
- 286 789 ÷ 2 = 143 394 + 1;
- 143 394 ÷ 2 = 71 697 + 0;
- 71 697 ÷ 2 = 35 848 + 1;
- 35 848 ÷ 2 = 17 924 + 0;
- 17 924 ÷ 2 = 8 962 + 0;
- 8 962 ÷ 2 = 4 481 + 0;
- 4 481 ÷ 2 = 2 240 + 1;
- 2 240 ÷ 2 = 1 120 + 0;
- 1 120 ÷ 2 = 560 + 0;
- 560 ÷ 2 = 280 + 0;
- 280 ÷ 2 = 140 + 0;
- 140 ÷ 2 = 70 + 0;
- 70 ÷ 2 = 35 + 0;
- 35 ÷ 2 = 17 + 1;
- 17 ÷ 2 = 8 + 1;
- 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.
587 345 680(10) = 10 0011 0000 0010 0010 1111 0001 0000(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 30.
- 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) is reserved for 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, 30,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 32.
5. Get the positive binary computer representation on 32 bits (4 Bytes):
If needed, add extra 0s in front (to the left) of the base 2 number, up to the required length, 32:
587 345 680(10) = 0010 0011 0000 0010 0010 1111 0001 0000
6. Get the negative integer number representation:
To get the negative integer number representation on 32 bits (4 Bytes),
... change the first bit (the leftmost), from 0 to 1...
-587 345 680(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-587 345 680(10) = 1010 0011 0000 0010 0010 1111 0001 0000
Spaces were used to group digits: for binary, by 4, for decimal, by 3.