Collatz Conjecture in R
Calculate the number of steps to reach 1 using the Collatz conjecture
exercism fetch r 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.
See this guide for instructions on how to setup your local R environment.
How to implement your solution
In each problem folder, there is a file named
<exercise_name>.R containing a function that returns a
NULL value. Place your implementation inside the body of the function.
How to run tests
Inside of RStudio, simply execute the
test_<exercise_name>.R script. This can be conveniently done with testthat's
auto_test function. Because exercism code and tests are in the same folder, use this same path for both
test_path parameters. On the command-line, you can also run
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.