What are the required steps to convert base 10 integer
number -702 985 453 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:
|-702 985 453| = 702 985 453
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;
- 702 985 453 ÷ 2 = 351 492 726 + 1;
- 351 492 726 ÷ 2 = 175 746 363 + 0;
- 175 746 363 ÷ 2 = 87 873 181 + 1;
- 87 873 181 ÷ 2 = 43 936 590 + 1;
- 43 936 590 ÷ 2 = 21 968 295 + 0;
- 21 968 295 ÷ 2 = 10 984 147 + 1;
- 10 984 147 ÷ 2 = 5 492 073 + 1;
- 5 492 073 ÷ 2 = 2 746 036 + 1;
- 2 746 036 ÷ 2 = 1 373 018 + 0;
- 1 373 018 ÷ 2 = 686 509 + 0;
- 686 509 ÷ 2 = 343 254 + 1;
- 343 254 ÷ 2 = 171 627 + 0;
- 171 627 ÷ 2 = 85 813 + 1;
- 85 813 ÷ 2 = 42 906 + 1;
- 42 906 ÷ 2 = 21 453 + 0;
- 21 453 ÷ 2 = 10 726 + 1;
- 10 726 ÷ 2 = 5 363 + 0;
- 5 363 ÷ 2 = 2 681 + 1;
- 2 681 ÷ 2 = 1 340 + 1;
- 1 340 ÷ 2 = 670 + 0;
- 670 ÷ 2 = 335 + 0;
- 335 ÷ 2 = 167 + 1;
- 167 ÷ 2 = 83 + 1;
- 83 ÷ 2 = 41 + 1;
- 41 ÷ 2 = 20 + 1;
- 20 ÷ 2 = 10 + 0;
- 10 ÷ 2 = 5 + 0;
- 5 ÷ 2 = 2 + 1;
- 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.
702 985 453(10) = 10 1001 1110 0110 1011 0100 1110 1101(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 30.
- 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, 30,
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:
702 985 453(10) = 0010 1001 1110 0110 1011 0100 1110 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...
-702 985 453(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-702 985 453(10) = 1010 1001 1110 0110 1011 0100 1110 1101
Spaces were used to group digits: for binary, by 4, for decimal, by 3.