Collatz Conjecture in Rust
Calculate the number of steps to reach 1 using the Collatz conjecture
exercism fetch rust 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.
Starting with n = 12, the steps would be as follows:
Resulting in 9 steps. So for input n = 12, the return value would be 9.
Refer to the exercism help page for Rust installation and learning resources.
Writing the Code
Execute the tests with:
$ cargo test
All but the first test have been ignored. After you get the first test to
pass, remove the ignore flag (
#[ignore]) from the next test and get the tests
to pass again. The test file is located in the
tests directory. You can
also remove the ignore flag from all the tests to get them to run all at once
if you wish.
Make sure to read the Modules chapter if you haven't already, it will help you with organizing your files.
Feedback, Issues, Pull Requests
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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.