Merge pull request #592 from ricemery/dart

Add darts exercise

config.json

@@ -1088,6 +1088,18 @@
         "strings",
         "transforming"
       ]
+    },
+    {
+      "slug": "darts",
+      "uuid": "939bfbf2-55c9-4c54-b2ef-3247bb6fc67c",
+      "core": false,
+      "unlocked_by": "sum-of-multiples",
+      "difficulty": 1,
+      "topics": [
+        "math",
+        "control_flow_if_else_statements",
+        "floating_point_numbers"
+      ]
     }
   ]
 }

exercises/darts/README.md

@@ -0,0 +1,33 @@
+# Darts
+
+Write a function that returns the earned points in a single toss of a Darts game.
+
+[Darts](https://en.wikipedia.org/wiki/Darts) is a game where players
+throw darts to a [target](https://en.wikipedia.org/wiki/Darts#/media/File:Darts_in_a_dartboard.jpg).
+
+In our particular instance of the game, the target rewards with 4 different amounts of points, depending on where the dart lands:
+
+* If the dart lands outside the target, player earns no points (0 points).
+* If the dart lands in the outer circle of the target, player earns 1 point.
+* If the dart lands in the middle circle of the target, player earns 5 points.
+* If the dart lands in the inner circle of the target, player earns 10 points.
+
+The outer circle has a radius of 10 units (This is equivalent to the total radius for the entire target), the middle circle a radius of 5 units, and the inner circle a radius of 1. Of course, they are all centered to the same point (That is, the circles are [concentric](http://mathworld.wolfram.com/ConcentricCircles.html)) defined by the coordinates (0, 0).
+
+Write a function that given a point in the target (defined by its `real` cartesian coordinates `x` and `y`), returns the correct amount earned by a dart landing in that point.
+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.
+
+For more detailed info about the Scala track see the [help
+page](http://exercism.io/languages/scala).
+
+
+## Source
+
+Inspired by an excersie created by a professor Della Paolera in Argentina
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.

exercises/darts/build.sbt

@@ -0,0 +1,3 @@
+scalaVersion := "2.12.1"
+
+libraryDependencies += "org.scalatest" %% "scalatest" % "3.0.1" % "test"

exercises/darts/example.scala

@@ -0,0 +1,11 @@
+object Darts {
+  def score(x: Double, y: Double): Int = {
+    val distance = math.sqrt(x * x + y * y)
+    distance match  {
+      case _ if distance <= 1.0 => 10
+      case _ if distance <= 5.0 => 5
+      case _ if distance <= 10.0 => 1
+      case _ => 0
+    }
+  }
+}

exercises/darts/src/test/scala/DartsTest.scala

@@ -0,0 +1,29 @@
+import org.scalatest.{Matchers, FunSuite}
+
+/** @version 1.0.0 */
+class DartsTest extends FunSuite with Matchers {
+
+  test("A dart lands outside the target") {
+    Darts.score(15.3, 13.2) should be (0)
+  }
+
+  test("A dart lands just in the border of the target") {
+    pending
+    Darts.score(10, 0) should be (1)
+  }
+
+  test("A dart lands in the middle circle") {
+    pending
+    Darts.score(3, 3.7) should be (5)
+  }
+
+  test("A dart lands right in the border between outside and middle circles") {
+    pending
+    Darts.score(0, 5) should be (5)
+  }
+
+  test("A dart lands in the inner circle") {
+    pending
+    Darts.score(0, 0) should be (10)
+  }
+}

testgen/src/main/scala/DartsTestGenerator.scala

@@ -0,0 +1,15 @@
+import java.io.File
+
+import testgen.TestSuiteBuilder._
+import testgen._
+
+object DartsTestGenerator {
+  def main(args: Array[String]): Unit = {
+    val file = new File("src/main/resources/darts.json")
+
+    val code = TestSuiteBuilder.build(file, fromLabeledTestFromInput("x", "y"))
+    println(s"-------------")
+    println(code)
+    println(s"-------------")
+  }
+}