What are the required steps to convert base 10 integer
number -1 999 999 893 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:
|-1 999 999 893| = 1 999 999 893
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;
- 1 999 999 893 ÷ 2 = 999 999 946 + 1;
- 999 999 946 ÷ 2 = 499 999 973 + 0;
- 499 999 973 ÷ 2 = 249 999 986 + 1;
- 249 999 986 ÷ 2 = 124 999 993 + 0;
- 124 999 993 ÷ 2 = 62 499 996 + 1;
- 62 499 996 ÷ 2 = 31 249 998 + 0;
- 31 249 998 ÷ 2 = 15 624 999 + 0;
- 15 624 999 ÷ 2 = 7 812 499 + 1;
- 7 812 499 ÷ 2 = 3 906 249 + 1;
- 3 906 249 ÷ 2 = 1 953 124 + 1;
- 1 953 124 ÷ 2 = 976 562 + 0;
- 976 562 ÷ 2 = 488 281 + 0;
- 488 281 ÷ 2 = 244 140 + 1;
- 244 140 ÷ 2 = 122 070 + 0;
- 122 070 ÷ 2 = 61 035 + 0;
- 61 035 ÷ 2 = 30 517 + 1;
- 30 517 ÷ 2 = 15 258 + 1;
- 15 258 ÷ 2 = 7 629 + 0;
- 7 629 ÷ 2 = 3 814 + 1;
- 3 814 ÷ 2 = 1 907 + 0;
- 1 907 ÷ 2 = 953 + 1;
- 953 ÷ 2 = 476 + 1;
- 476 ÷ 2 = 238 + 0;
- 238 ÷ 2 = 119 + 0;
- 119 ÷ 2 = 59 + 1;
- 59 ÷ 2 = 29 + 1;
- 29 ÷ 2 = 14 + 1;
- 14 ÷ 2 = 7 + 0;
- 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.
1 999 999 893(10) = 111 0111 0011 0101 1001 0011 1001 0101(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:
1 999 999 893(10) = 0111 0111 0011 0101 1001 0011 1001 0101
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...
-1 999 999 893(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 999 999 893(10) = 1111 0111 0011 0101 1001 0011 1001 0101
Spaces were used to group digits: for binary, by 4, for decimal, by 3.