What are the required steps to convert base 10 integer
number -1 870 134 189 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:
|-1 870 134 189| = 1 870 134 189
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;
- 1 870 134 189 ÷ 2 = 935 067 094 + 1;
- 935 067 094 ÷ 2 = 467 533 547 + 0;
- 467 533 547 ÷ 2 = 233 766 773 + 1;
- 233 766 773 ÷ 2 = 116 883 386 + 1;
- 116 883 386 ÷ 2 = 58 441 693 + 0;
- 58 441 693 ÷ 2 = 29 220 846 + 1;
- 29 220 846 ÷ 2 = 14 610 423 + 0;
- 14 610 423 ÷ 2 = 7 305 211 + 1;
- 7 305 211 ÷ 2 = 3 652 605 + 1;
- 3 652 605 ÷ 2 = 1 826 302 + 1;
- 1 826 302 ÷ 2 = 913 151 + 0;
- 913 151 ÷ 2 = 456 575 + 1;
- 456 575 ÷ 2 = 228 287 + 1;
- 228 287 ÷ 2 = 114 143 + 1;
- 114 143 ÷ 2 = 57 071 + 1;
- 57 071 ÷ 2 = 28 535 + 1;
- 28 535 ÷ 2 = 14 267 + 1;
- 14 267 ÷ 2 = 7 133 + 1;
- 7 133 ÷ 2 = 3 566 + 1;
- 3 566 ÷ 2 = 1 783 + 0;
- 1 783 ÷ 2 = 891 + 1;
- 891 ÷ 2 = 445 + 1;
- 445 ÷ 2 = 222 + 1;
- 222 ÷ 2 = 111 + 0;
- 111 ÷ 2 = 55 + 1;
- 55 ÷ 2 = 27 + 1;
- 27 ÷ 2 = 13 + 1;
- 13 ÷ 2 = 6 + 1;
- 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.
1 870 134 189(10) = 110 1111 0111 0111 1111 1011 1010 1101(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 31.
- 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, 31,
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:
1 870 134 189(10) = 0110 1111 0111 0111 1111 1011 1010 1101
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...
-1 870 134 189(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 870 134 189(10) = 1110 1111 0111 0111 1111 1011 1010 1101
Spaces were used to group digits: for binary, by 4, for decimal, by 3.