What are the required steps to convert base 10 integer
number -1 146 467 738 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:
|-1 146 467 738| = 1 146 467 738
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;
- 1 146 467 738 ÷ 2 = 573 233 869 + 0;
- 573 233 869 ÷ 2 = 286 616 934 + 1;
- 286 616 934 ÷ 2 = 143 308 467 + 0;
- 143 308 467 ÷ 2 = 71 654 233 + 1;
- 71 654 233 ÷ 2 = 35 827 116 + 1;
- 35 827 116 ÷ 2 = 17 913 558 + 0;
- 17 913 558 ÷ 2 = 8 956 779 + 0;
- 8 956 779 ÷ 2 = 4 478 389 + 1;
- 4 478 389 ÷ 2 = 2 239 194 + 1;
- 2 239 194 ÷ 2 = 1 119 597 + 0;
- 1 119 597 ÷ 2 = 559 798 + 1;
- 559 798 ÷ 2 = 279 899 + 0;
- 279 899 ÷ 2 = 139 949 + 1;
- 139 949 ÷ 2 = 69 974 + 1;
- 69 974 ÷ 2 = 34 987 + 0;
- 34 987 ÷ 2 = 17 493 + 1;
- 17 493 ÷ 2 = 8 746 + 1;
- 8 746 ÷ 2 = 4 373 + 0;
- 4 373 ÷ 2 = 2 186 + 1;
- 2 186 ÷ 2 = 1 093 + 0;
- 1 093 ÷ 2 = 546 + 1;
- 546 ÷ 2 = 273 + 0;
- 273 ÷ 2 = 136 + 1;
- 136 ÷ 2 = 68 + 0;
- 68 ÷ 2 = 34 + 0;
- 34 ÷ 2 = 17 + 0;
- 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.
1 146 467 738(10) = 100 0100 0101 0101 1011 0101 1001 1010(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:
1 146 467 738(10) = 0100 0100 0101 0101 1011 0101 1001 1010
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...
-1 146 467 738(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-1 146 467 738(10) = 1100 0100 0101 0101 1011 0101 1001 1010
Spaces were used to group digits: for binary, by 4, for decimal, by 3.