Your task is to convert a number into a string that contains raindrop sounds corresponding to certain potential factors. A factor is a number that evenly divides into another number, leaving no remainder. The simplest way to test if a one number is a factor of another is to use the modulo operation.
The rules of raindrops
are that if a given number:
The Scala exercises assume an SBT project scheme. The exercise solution source should be placed within the exercise directory/src/main/scala. The exercise unit tests can be found within the exercise directory/src/test/scala.
To run the tests simply run the command sbt test
in the exercise directory.
Please see the learning and installation pages if you need any help.
A variation on FizzBuzz, a famous technical interview question that is intended to weed out potential candidates. That question is itself derived from Fizz Buzz, a popular children's game for teaching division. https://en.wikipedia.org/wiki/Fizz_buzz
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
import org.scalatest.{Matchers, FunSuite}
/** @version 1.1.0 */
class RaindropsTest extends FunSuite with Matchers {
test("the sound for 1 is 1") {
Raindrops.convert(1) should be ("1")
}
test("the sound for 3 is Pling") {
pending
Raindrops.convert(3) should be ("Pling")
}
test("the sound for 5 is Plang") {
pending
Raindrops.convert(5) should be ("Plang")
}
test("the sound for 7 is Plong") {
pending
Raindrops.convert(7) should be ("Plong")
}
test("the sound for 6 is Pling as it has a factor 3") {
pending
Raindrops.convert(6) should be ("Pling")
}
test("2 to the power 3 does not make a raindrop sound as 3 is the exponent not the base") {
pending
Raindrops.convert(8) should be ("8")
}
test("the sound for 9 is Pling as it has a factor 3") {
pending
Raindrops.convert(9) should be ("Pling")
}
test("the sound for 10 is Plang as it has a factor 5") {
pending
Raindrops.convert(10) should be ("Plang")
}
test("the sound for 14 is Plong as it has a factor of 7") {
pending
Raindrops.convert(14) should be ("Plong")
}
test("the sound for 15 is PlingPlang as it has factors 3 and 5") {
pending
Raindrops.convert(15) should be ("PlingPlang")
}
test("the sound for 21 is PlingPlong as it has factors 3 and 7") {
pending
Raindrops.convert(21) should be ("PlingPlong")
}
test("the sound for 25 is Plang as it has a factor 5") {
pending
Raindrops.convert(25) should be ("Plang")
}
test("the sound for 27 is Pling as it has a factor 3") {
pending
Raindrops.convert(27) should be ("Pling")
}
test("the sound for 35 is PlangPlong as it has factors 5 and 7") {
pending
Raindrops.convert(35) should be ("PlangPlong")
}
test("the sound for 49 is Plong as it has a factor 7") {
pending
Raindrops.convert(49) should be ("Plong")
}
test("the sound for 52 is 52") {
pending
Raindrops.convert(52) should be ("52")
}
test("the sound for 105 is PlingPlangPlong as it has factors 3, 5 and 7") {
pending
Raindrops.convert(105) should be ("PlingPlangPlong")
}
test("the sound for 3125 is Plang as it has a factor 5") {
pending
Raindrops.convert(3125) should be ("Plang")
}
}
object Raindrops {
def convert(n: Int): String = {
var result = ""
if (n % 3 == 0)
result += "Pling"
if (n % 5 == 0)
result += "Plang"
if (n % 7 == 0)
result += "Plong"
if (result == "") n.toString else result
}
}
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