Raindrops

Raindrops

Medium

Introduction

Raindrops is a slightly more complex version of the FizzBuzz challenge, a classic interview question.

Instructions

Your task is to convert a number into its corresponding raindrop sounds.

If a given number:

  • is divisible by 3, add "Pling" to the result.
  • is divisible by 5, add "Plang" to the result.
  • is divisible by 7, add "Plong" to the result.
  • is not divisible by 3, 5, or 7, the result should be the number as a string.

Examples

  • 28 is divisible by 7, but not 3 or 5, so the result would be "Plong".
  • 30 is divisible by 3 and 5, but not 7, so the result would be "PlingPlang".
  • 34 is not divisible by 3, 5, or 7, so the result would be "34".
Note

A common way to test if one number is evenly divisible by another is to compare the remainder or modulus to zero. Most languages provide operators or functions for one (or both) of these.

Running and testing your solutions

From the command line

Simply type make chez if you're using ChezScheme or make guile if you're using GNU Guile. Sometimes the name for the scheme binary on your system will differ from the defaults. When this is the case, you'll need to tell make by running make chez chez=your-chez-binary or make guile guile=your-guile-binary.

From a REPL

  • Enter (load "test.scm") at the repl prompt.
  • Develop your solution in raindrops.scm reloading as you go.
  • Run (test) to check your solution.

Failed Test Cases

If some of the test cases fail, you should see the failing input and the expected output. The failing input is presented as a list because the tests call your solution by (apply raindrops input-list). To learn more about apply see The Scheme Programming Language -- Chapter 5

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