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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.
## Running the tests
1. Go to the root of your PHP exercise directory, which is `<EXERCISM_WORKSPACE>/php`.
To find the Exercism workspace run
% exercism debug | grep Workspace
1. Get [PHPUnit] if you don't have it already.
% wget --no-check-certificate https://phar.phpunit.de/phpunit.phar
% chmod +x phpunit.phar
2. Execute the tests:
% ./phpunit.phar collatz-conjecture/collatz-conjecture_test.php
[PHPUnit]: http://phpunit.de
## 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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