What are the required steps to convert base 10 integer
number -14 234 932 494 215 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:
|-14 234 932 494 215| = 14 234 932 494 215
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;
- 14 234 932 494 215 ÷ 2 = 7 117 466 247 107 + 1;
- 7 117 466 247 107 ÷ 2 = 3 558 733 123 553 + 1;
- 3 558 733 123 553 ÷ 2 = 1 779 366 561 776 + 1;
- 1 779 366 561 776 ÷ 2 = 889 683 280 888 + 0;
- 889 683 280 888 ÷ 2 = 444 841 640 444 + 0;
- 444 841 640 444 ÷ 2 = 222 420 820 222 + 0;
- 222 420 820 222 ÷ 2 = 111 210 410 111 + 0;
- 111 210 410 111 ÷ 2 = 55 605 205 055 + 1;
- 55 605 205 055 ÷ 2 = 27 802 602 527 + 1;
- 27 802 602 527 ÷ 2 = 13 901 301 263 + 1;
- 13 901 301 263 ÷ 2 = 6 950 650 631 + 1;
- 6 950 650 631 ÷ 2 = 3 475 325 315 + 1;
- 3 475 325 315 ÷ 2 = 1 737 662 657 + 1;
- 1 737 662 657 ÷ 2 = 868 831 328 + 1;
- 868 831 328 ÷ 2 = 434 415 664 + 0;
- 434 415 664 ÷ 2 = 217 207 832 + 0;
- 217 207 832 ÷ 2 = 108 603 916 + 0;
- 108 603 916 ÷ 2 = 54 301 958 + 0;
- 54 301 958 ÷ 2 = 27 150 979 + 0;
- 27 150 979 ÷ 2 = 13 575 489 + 1;
- 13 575 489 ÷ 2 = 6 787 744 + 1;
- 6 787 744 ÷ 2 = 3 393 872 + 0;
- 3 393 872 ÷ 2 = 1 696 936 + 0;
- 1 696 936 ÷ 2 = 848 468 + 0;
- 848 468 ÷ 2 = 424 234 + 0;
- 424 234 ÷ 2 = 212 117 + 0;
- 212 117 ÷ 2 = 106 058 + 1;
- 106 058 ÷ 2 = 53 029 + 0;
- 53 029 ÷ 2 = 26 514 + 1;
- 26 514 ÷ 2 = 13 257 + 0;
- 13 257 ÷ 2 = 6 628 + 1;
- 6 628 ÷ 2 = 3 314 + 0;
- 3 314 ÷ 2 = 1 657 + 0;
- 1 657 ÷ 2 = 828 + 1;
- 828 ÷ 2 = 414 + 0;
- 414 ÷ 2 = 207 + 0;
- 207 ÷ 2 = 103 + 1;
- 103 ÷ 2 = 51 + 1;
- 51 ÷ 2 = 25 + 1;
- 25 ÷ 2 = 12 + 1;
- 12 ÷ 2 = 6 + 0;
- 6 ÷ 2 = 3 + 0;
- 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.
14 234 932 494 215(10) = 1100 1111 0010 0101 0100 0001 1000 0011 1111 1000 0111(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 44.
- 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, 44,
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:
14 234 932 494 215(10) = 0000 0000 0000 0000 0000 1100 1111 0010 0101 0100 0001 1000 0011 1111 1000 0111
6. Get the negative integer number representation:
To get the negative integer number representation on 64 bits (8 Bytes),
... change the first bit (the leftmost), from 0 to 1...
-14 234 932 494 215(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-14 234 932 494 215(10) = 1000 0000 0000 0000 0000 1100 1111 0010 0101 0100 0001 1000 0011 1111 1000 0111
Spaces were used to group digits: for binary, by 4, for decimal, by 3.