# Secret Handshake > There are 10 types of people in the world: Those who understand > binary, and those who don't. You and your fellow cohort of those in the "know" when it comes to binary decide to come up with a secret "handshake". ``` 1 = wink 10 = double blink 100 = close your eyes 1000 = jump 10000 = Reverse the order of the operations in the secret handshake. ``` Given a decimal number, convert it to the appropriate sequence of events for a secret handshake. Here's a couple of examples: Given the input 3, the function would return the array ["wink", "double blink"] because 3 is 11 in binary. Given the input 19, the function would return the array ["double blink", "wink"] because 19 is 10011 in binary. Notice that the addition of 16 (10000 in binary) has caused the array to be reversed. ## Installation See [this guide](https://github.com/exercism/xr/blob/master/docs/INSTALLATION.md) for instructions on how to setup your local R environment. ## How to implement your solution In each problem folder, there is a file named `.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_.R` script. This can be conveniently done with [testthat's `auto_test` function](https://www.rdocumentation.org/packages/testthat/topics/auto_test). Because exercism code and tests are in the same folder, use this same path for both `code_path` and `test_path` parameters. On the command-line, you can also run `Rscript test_.R`. ## Source Bert, in Mary Poppins [http://www.imdb.com/character/ch0011238/quotes](http://www.imdb.com/character/ch0011238/quotes) ## Submitting Incomplete Solutions It's possible to submit an incomplete solution so you can see how others have completed the exercise.