What are the required steps to convert base 10 integer
number 111 111 111 111 111 155 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. 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;
- 111 111 111 111 111 155 ÷ 2 = 55 555 555 555 555 577 + 1;
- 55 555 555 555 555 577 ÷ 2 = 27 777 777 777 777 788 + 1;
- 27 777 777 777 777 788 ÷ 2 = 13 888 888 888 888 894 + 0;
- 13 888 888 888 888 894 ÷ 2 = 6 944 444 444 444 447 + 0;
- 6 944 444 444 444 447 ÷ 2 = 3 472 222 222 222 223 + 1;
- 3 472 222 222 222 223 ÷ 2 = 1 736 111 111 111 111 + 1;
- 1 736 111 111 111 111 ÷ 2 = 868 055 555 555 555 + 1;
- 868 055 555 555 555 ÷ 2 = 434 027 777 777 777 + 1;
- 434 027 777 777 777 ÷ 2 = 217 013 888 888 888 + 1;
- 217 013 888 888 888 ÷ 2 = 108 506 944 444 444 + 0;
- 108 506 944 444 444 ÷ 2 = 54 253 472 222 222 + 0;
- 54 253 472 222 222 ÷ 2 = 27 126 736 111 111 + 0;
- 27 126 736 111 111 ÷ 2 = 13 563 368 055 555 + 1;
- 13 563 368 055 555 ÷ 2 = 6 781 684 027 777 + 1;
- 6 781 684 027 777 ÷ 2 = 3 390 842 013 888 + 1;
- 3 390 842 013 888 ÷ 2 = 1 695 421 006 944 + 0;
- 1 695 421 006 944 ÷ 2 = 847 710 503 472 + 0;
- 847 710 503 472 ÷ 2 = 423 855 251 736 + 0;
- 423 855 251 736 ÷ 2 = 211 927 625 868 + 0;
- 211 927 625 868 ÷ 2 = 105 963 812 934 + 0;
- 105 963 812 934 ÷ 2 = 52 981 906 467 + 0;
- 52 981 906 467 ÷ 2 = 26 490 953 233 + 1;
- 26 490 953 233 ÷ 2 = 13 245 476 616 + 1;
- 13 245 476 616 ÷ 2 = 6 622 738 308 + 0;
- 6 622 738 308 ÷ 2 = 3 311 369 154 + 0;
- 3 311 369 154 ÷ 2 = 1 655 684 577 + 0;
- 1 655 684 577 ÷ 2 = 827 842 288 + 1;
- 827 842 288 ÷ 2 = 413 921 144 + 0;
- 413 921 144 ÷ 2 = 206 960 572 + 0;
- 206 960 572 ÷ 2 = 103 480 286 + 0;
- 103 480 286 ÷ 2 = 51 740 143 + 0;
- 51 740 143 ÷ 2 = 25 870 071 + 1;
- 25 870 071 ÷ 2 = 12 935 035 + 1;
- 12 935 035 ÷ 2 = 6 467 517 + 1;
- 6 467 517 ÷ 2 = 3 233 758 + 1;
- 3 233 758 ÷ 2 = 1 616 879 + 0;
- 1 616 879 ÷ 2 = 808 439 + 1;
- 808 439 ÷ 2 = 404 219 + 1;
- 404 219 ÷ 2 = 202 109 + 1;
- 202 109 ÷ 2 = 101 054 + 1;
- 101 054 ÷ 2 = 50 527 + 0;
- 50 527 ÷ 2 = 25 263 + 1;
- 25 263 ÷ 2 = 12 631 + 1;
- 12 631 ÷ 2 = 6 315 + 1;
- 6 315 ÷ 2 = 3 157 + 1;
- 3 157 ÷ 2 = 1 578 + 1;
- 1 578 ÷ 2 = 789 + 0;
- 789 ÷ 2 = 394 + 1;
- 394 ÷ 2 = 197 + 0;
- 197 ÷ 2 = 98 + 1;
- 98 ÷ 2 = 49 + 0;
- 49 ÷ 2 = 24 + 1;
- 24 ÷ 2 = 12 + 0;
- 12 ÷ 2 = 6 + 0;
- 6 ÷ 2 = 3 + 0;
- 3 ÷ 2 = 1 + 1;
- 1 ÷ 2 = 0 + 1;
2. Construct the base 2 representation of the positive number:
Take all the remainders starting from the bottom of the list constructed above.
111 111 111 111 111 155(10) = 1 1000 1010 1011 1110 1111 0111 1000 0100 0110 0000 0111 0001 1111 0011(2)
3. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 57.
- 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, 57,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 64.
4. 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:
111 111 111 111 111 155(10) Base 10 integer number converted and written as a signed binary code (in base 2):
111 111 111 111 111 155(10) = 0000 0001 1000 1010 1011 1110 1111 0111 1000 0100 0110 0000 0111 0001 1111 0011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.