What are the required steps to convert base 10 integer
number -757 071 451 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:
|-757 071 451| = 757 071 451
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;
- 757 071 451 ÷ 2 = 378 535 725 + 1;
- 378 535 725 ÷ 2 = 189 267 862 + 1;
- 189 267 862 ÷ 2 = 94 633 931 + 0;
- 94 633 931 ÷ 2 = 47 316 965 + 1;
- 47 316 965 ÷ 2 = 23 658 482 + 1;
- 23 658 482 ÷ 2 = 11 829 241 + 0;
- 11 829 241 ÷ 2 = 5 914 620 + 1;
- 5 914 620 ÷ 2 = 2 957 310 + 0;
- 2 957 310 ÷ 2 = 1 478 655 + 0;
- 1 478 655 ÷ 2 = 739 327 + 1;
- 739 327 ÷ 2 = 369 663 + 1;
- 369 663 ÷ 2 = 184 831 + 1;
- 184 831 ÷ 2 = 92 415 + 1;
- 92 415 ÷ 2 = 46 207 + 1;
- 46 207 ÷ 2 = 23 103 + 1;
- 23 103 ÷ 2 = 11 551 + 1;
- 11 551 ÷ 2 = 5 775 + 1;
- 5 775 ÷ 2 = 2 887 + 1;
- 2 887 ÷ 2 = 1 443 + 1;
- 1 443 ÷ 2 = 721 + 1;
- 721 ÷ 2 = 360 + 1;
- 360 ÷ 2 = 180 + 0;
- 180 ÷ 2 = 90 + 0;
- 90 ÷ 2 = 45 + 0;
- 45 ÷ 2 = 22 + 1;
- 22 ÷ 2 = 11 + 0;
- 11 ÷ 2 = 5 + 1;
- 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.
757 071 451(10) = 10 1101 0001 1111 1111 1110 0101 1011(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:
757 071 451(10) = 0010 1101 0001 1111 1111 1110 0101 1011
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...
-757 071 451(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-757 071 451(10) = 1010 1101 0001 1111 1111 1110 0101 1011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.