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Contents

# 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.

## Setup

There are two different methods of getting set up to run the tests with Objective-C:

- Create an Xcode project with a test target which will run the tests.
- Use the ruby gem `objc` as a test runner utility.

Both are described in more detail here: http://exercism.io/languages/objective-c

### Submitting Exercises

When submitting an exercise, make sure your solution file is in the same directory as the test code.

The submit command will look something like:

```shell
exercism submit <path-to-exercism-workspace>/objective-c/collatz-conjecture/CollatzConjecture.m
```

You can find the Exercism workspace by running `exercism debug` and looking for the line beginning
with Workspace.

## 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.

Version data entries

75 entries across 75 versions & 1 rubygems

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trackler-2.2.1.180 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.179 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.178 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.177 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.176 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.175 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.174 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.173 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.172 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.171 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.170 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.169 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.167 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.166 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.165 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.164 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.163 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.162 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.161 tracks/objective-c/exercises/collatz-conjecture/README.md
trackler-2.2.1.160 tracks/objective-c/exercises/collatz-conjecture/README.md