# Collatz Conjecture in Python

#### Calculate the number of steps to reach 1 using the Collatz conjecture

1 | ```
exercism fetch python collatz-conjecture
``` |

# 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:

- 12
- 6
- 3
- 10
- 5
- 16
- 8
- 4
- 2
- 1

Resulting in 9 steps. So for input n = 12, the return value would be 9.

## Notes

The Collatz Conjecture is only concerned with strictly positive integers, so your solution should raise a `ValueError`

with a meaningful message if given 0 or a negative integer.

## Submitting Exercises

Note that, when trying to submit an exercise, make sure the solution is in the `exercism/python/<exerciseName>`

directory.

For example, if you're submitting `bob.py`

for the Bob exercise, the submit command would be something like `exercism submit <path_to_exercism_dir>/python/bob/bob.py`

.

For more detailed information about running tests, code style and linting, please see the help page.

## Source

An unsolved problem in mathematics named after mathematician Lothar Collatz 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.