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# Collatz Conjecture
The Collatz Conjecture or 3x+1 problem can be summarized as follows:
Take any positive integer n. If n is even, divide n by 2 to get n / 2. If n is
odd, multiply n by 3 and add 1 to get 3n + 1. Repeat the process indefinitely.
The conjecture states that no matter which number you start with, you will
always reach 1 eventually.
Given a number n, return the number of steps required to reach 1.
## Examples
Starting with n = 12, the steps would be as follows:
0. 12
1. 6
2. 3
3. 10
4. 5
5. 16
6. 8
7. 4
8. 2
9. 1
Resulting in 9 steps. So for input n = 12, the return value would be 9.
## Getting Started
Make sure you have read the
[C page](http://exercism.io/languages/c) on the Exercism site. This covers
the basic information on setting up the development environment expected
by the exercises.
## Passing the Tests
Get the first test compiling, linking and passing by following the [three
rules of test-driven development][3-tdd-rules].
The included makefile can be used to create and run the tests using the `test`
task.
make test
Create just the functions you need to satisfy any compiler errors and get the
test to fail. Then write just enough code to get the test to pass. Once you've
done that, move onto the next test.
[3-tdd-rules]: http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd
As you progress through the tests, take the time to refactor your
implementation for readability and expressiveness and then go on to the next
test.
Try to use standard C99 facilities in preference to writing your own
low-level algorithms or facilities by hand.
## Source
An unsolved problem in mathematics named after mathematician Lothar Collatz [https://en.wikipedia.org/wiki/3x_%2B_1_problem](https://en.wikipedia.org/wiki/3x_%2B_1_problem)
## Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
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