the only thing that you need to be able to do is divide by 2 with a remainder.
- divide the number by 2,
- get the quotient for the next iteration,
- remember the remainder for the binary digit,
- repeat the steps until the quotient is equal to 0,
- write the remainders in the reverse order.
| Quotient | Remainder |
|---|---|
| 42 | 0 |
| 21 | 1 |
| 10 | 0 |
| 5 | 1 |
| 2 | 0 |
| 1 | 1 |
42 in base 2 is = 101010
- make the list of all the powers of 2 that are smaller or equal to the number
- subtract the biggest power from the number if it is possible
- get the result for the next iteration
- remember the 1 if you did the subtraction. If not, remember the 0
- repeat the steps until the end of the list.
- 42 in base 2 using subtraction method
| 32 | 16 | 8 | 4 | 2 | 1 |
|---|---|---|---|---|---|
| 1 | 0 | 1 | 0 | 1 | 0 |