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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 tests
Execute the tests with:
```bash
$ elixir bob_test.exs
```
(Replace `bob_test.exs` with the name of the test file.)
### Pending tests
In the test suites, all but the first test have been skipped.
Once you get a test passing, you can unskip the next one by
commenting out the relevant `@tag :pending` with a `#` symbol.
For example:
```elixir
# @tag :pending
test "shouting" do
assert Bob.hey("WATCH OUT!") == "Whoa, chill out!"
end
```
Or, you can enable all the tests by commenting out the
`ExUnit.configure` line in the test suite.
```elixir
# ExUnit.configure exclude: :pending, trace: true
```
For more detailed information about the Elixir track, please
see the [help page](http://exercism.io/languages/elixir).
## 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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