Change exercises

- All exercises share the same `sbt` build definition
- Exercises 2 demonstrates a use case for `cmtc pull-template`

.gitignore

@@ -1,13 +1,20 @@
 *.class
 *.log
 .bookmark
-
-# Metals/BSP
+hypriot.img
+collectedLogs/
+collectedLogs.zip
+
+# VSCode specific
+.vscode
+*.code-workspace
+
+# Metals/Bloop/sbt BSP specific
+.bloop/
+.metals/
+.swp
 .bsp
-metals.sbt
-
-# scala-cli
-
+**/project/metals.sbt
 **/.scala-build
 
 # sbt specific
@@ -29,6 +36,8 @@ project/plugins/project/
 .classpath
 .project
 .settings/
+.cache-main
+.cache-tests
 
 # Intellij specific
 *.iml
@@ -40,4 +49,8 @@ project/plugins/project/
 *.sublime-workspace
 
 # OS specific
-.DS_Store
+**/.DS_Store
+**/__MACOSX
+
+# Other
+Preci*.pdf

exercises/exercise_001_initial_state/.scalafmt.conf

@@ -0,0 +1,51 @@
+version         = 3.7.2
+runner.dialect  = scala3
+
+style                               = defaultWithAlign
+indentOperator.preset               = akka
+maxColumn                           = 120
+rewrite.rules                       = [RedundantParens, AvoidInfix]
+align.tokens                        = [{code = "=>", owner = "Case"}]
+align.openParenDefnSite             = false
+align.openParenCallSite             = false
+optIn.breakChainOnFirstMethodDot    = false
+optIn.configStyleArguments          = false
+danglingParentheses.defnSite        = false
+danglingParentheses.callSite        = false
+rewrite.neverInfix.excludeFilters   = [
+  and
+  min
+  max
+  until
+  to
+  by
+  eq
+  ne
+  "should.*"
+  "contain.*"
+  "must.*"
+  in
+  ignore
+  be
+  taggedAs
+  thrownBy
+  synchronized
+  have
+  when
+  size
+  only
+  noneOf
+  oneElementOf
+  noElementsOf
+  atLeastOneElementOf
+  atMostOneElementOf
+  allElementsOf
+  inOrderElementsOf
+  theSameElementsAs
+  message
+]
+rewriteTokens = {
+  "⇒": "=>"
+  "→": "->"
+  "←": "<-"
+}

exercises/exercise_001_initial_state/README.md

@@ -0,0 +1,17 @@
+# Getting started with Scala 3
+
+# Running "Hello World" application
+
+We start with the simplest of simplest program.
+
+Your task is to verify that the program prints
+"Hello, world!" on standard out.
+
+# Steps
+
+- In a terminal, cd into the root folder of the
+  exercise project
+- Start an `sbt` session
+- Execute the main method by issuing the `run`
+  command at the `sbt` prompt
+

exercises/exercise_001_initial_state/build.sbt

@@ -0,0 +1,4 @@
+scalaVersion := "3.3.0"
+
+libraryDependencies ++=
+  Seq("org.scalatest" %% "scalatest" % "3.2.16")

exercises/exercise_001_initial_state/project/build.properties

@@ -0,0 +1 @@
+sbt.version=1.9.4

exercises/exercise_001_initial_state/project/plugins.sbt

@@ -0,0 +1 @@
+addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.0")

exercises/exercise_002_adding_a_build_definition/src/main/scala/Hello.scala → exercises/exercise_001_initial_state/src/main/scala/Hello.scala

@@ -1,3 +1,2 @@
-
 @main def main(): Unit =
   println(s"Hello, world!")

exercises/exercise_002_calculating_with_prime_numbers/.scalafmt.conf

@@ -0,0 +1,51 @@
+version         = 3.7.2
+runner.dialect  = scala3
+
+style                               = defaultWithAlign
+indentOperator.preset               = akka
+maxColumn                           = 120
+rewrite.rules                       = [RedundantParens, AvoidInfix]
+align.tokens                        = [{code = "=>", owner = "Case"}]
+align.openParenDefnSite             = false
+align.openParenCallSite             = false
+optIn.breakChainOnFirstMethodDot    = false
+optIn.configStyleArguments          = false
+danglingParentheses.defnSite        = false
+danglingParentheses.callSite        = false
+rewrite.neverInfix.excludeFilters   = [
+  and
+  min
+  max
+  until
+  to
+  by
+  eq
+  ne
+  "should.*"
+  "contain.*"
+  "must.*"
+  in
+  ignore
+  be
+  taggedAs
+  thrownBy
+  synchronized
+  have
+  when
+  size
+  only
+  noneOf
+  oneElementOf
+  noElementsOf
+  atLeastOneElementOf
+  atMostOneElementOf
+  allElementsOf
+  inOrderElementsOf
+  theSameElementsAs
+  message
+]
+rewriteTokens = {
+  "⇒": "=>"
+  "→": "->"
+  "←": "<-"
+}

exercises/exercise_002_calculating_with_prime_numbers/README.md

@@ -0,0 +1,25 @@
+# Calculating the sum of a series of consecutive prime numbers
+
+Your task is to calculate the sum of all the prime numbers
+smaller than 3,000,000
+
+You can write your own Prime number generator, but you can also
+use one that is provided by executing the following `cmtc` command
+on the command line:
+
+`cmtc pull-template src/main/scala/primes/EratosthenesSieve.scala`
+
+Have a look at the provided class and look at
+how you can use it to calculate a series of prime
+numbers starting from 2 upto a given number.
+
+# Steps
+
+- Create a new object `SumOfPrimes`
+- Define a method `sumOfPrimesBelow` with a single parameter
+ `limit` of type `Int`.
+- Implement the method to return the sum of all primes numbers
+  below `limit`.
+- What should the return type of `sumOfPrimesBelow` be?
+
+- Run `test` from the `sbt` prompt and check if all tests pass.

exercises/exercise_002_calculating_with_prime_numbers/build.sbt

@@ -0,0 +1,4 @@
+scalaVersion := "3.3.0"
+
+libraryDependencies ++=
+  Seq("org.scalatest" %% "scalatest" % "3.2.16")

exercises/exercise_002_calculating_with_prime_numbers/project/build.properties

@@ -0,0 +1 @@
+sbt.version=1.9.4

exercises/exercise_002_calculating_with_prime_numbers/project/plugins.sbt

@@ -0,0 +1 @@
+addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.0")

exercises/exercise_001_getting_started/src/main/scala/Hello.scala → exercises/exercise_002_calculating_with_prime_numbers/src/main/scala/Hello.scala

@@ -1,3 +1,2 @@
-
 @main def main(): Unit =
   println(s"Hello, world!")

exercises/exercise_002_calculating_with_prime_numbers/src/main/scala/primes/EratosthenesSieve.scala

@@ -0,0 +1,31 @@
+package primes
+
+import collection.mutable.ArrayBuffer
+
+/** A memory intensive, but very fast implementation of Eratosthenes' Sieve using a mutable collection
+  *
+  * Taken from: https://lombardo-chcg.github.io/code-challenge/2017/10/09/sieve-of-eratosthenes.html
+  */
+
+class EratosthenesSieve:
+  def primesUnder(n: Int): List[Int] =
+    // Input: an integer n > 1.
+    if n <= 1 then List()
+    else {
+      // Let A be an array of Boolean values, indexed by integers 2 to n, initially all set to true.
+      val numbers = ArrayBuffer.fill(n + 1)(true)
+      // for i = 2, 3, 4, ..., not exceeding √n: if A[i] is true:
+      for (i <- 2 to Math.sqrt(n).toInt if numbers(i)) {
+        // for j = i2, i2+i, i2+2i, i2+3i, ..., not exceeding n:
+        for (j <- (i * i) to n by i) {
+          // A[j] := false.
+          numbers.update(j, false)
+        }
+      }
+
+      // Output: all i such that A[i] is true.
+      (for (m <- numbers.indices if numbers(m)) yield m)
+        .drop(2) // handling the 'off by 2' problem of the 0th index'ed array
+        .takeWhile(_ < n)
+        .toList
+    }

exercises/exercise_002_calculating_with_prime_numbers/src/main/scala/primes/Primes.scala

@@ -0,0 +1,9 @@
+package primes
+
+object Primes {
+  def sumOfPrimesBelow(limit: Int): BigInt =
+    val primesBelow = EratosthenesSieve().primesUnder(limit)
+    primesBelow.foldLeft(BigInt(0)) { case (sum, n) =>
+      sum + n
+    }
+}

exercises/exercise_002_calculating_with_prime_numbers/src/test/scala/primes/EratosthenesSieveSpec.scala

@@ -0,0 +1,28 @@
+package primes
+
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+
+class EratosthenesSieveSpec extends AnyFlatSpec with Matchers {
+  it should "return a list of all primes under a given number" in {
+    val expected30 = List(2, 3, 5, 7, 11, 13, 17, 19, 23, 29)
+    val expected100 =
+      List(2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97)
+    val expected1000 = List(2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89,
+      97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211,
+      223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331, 337, 347, 349,
+      353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463, 467, 479, 487,
+      491, 499, 503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 601, 607, 613, 617, 619, 631, 641,
+      643, 647, 653, 659, 661, 673, 677, 683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 797,
+      809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877, 881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953,
+      967, 971, 977, 983, 991, 997)
+    val primeCalculator = new EratosthenesSieve
+    primeCalculator.primesUnder(1) should equal(List())
+    primeCalculator.primesUnder(2) should equal(List())
+    primeCalculator.primesUnder(3) should equal(List(2))
+    primeCalculator.primesUnder(4) should equal(List(2, 3))
+    primeCalculator.primesUnder(30) should equal(expected30)
+    primeCalculator.primesUnder(100) should equal(expected100)
+    primeCalculator.primesUnder(1000) should equal(expected1000)
+  }
+}

exercises/exercise_002_calculating_with_prime_numbers/src/test/scala/primes/PrimesSpec.scala

@@ -0,0 +1,19 @@
+package primes
+
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+
+class PrimesSpec extends AnyFlatSpec with Matchers {
+  it should "calculate the correct sum of all primes smaller than 3,000,000" in {
+    val expectedSum = BigInt("312471072265")
+    val calculatedSum = Primes.sumOfPrimesBelow(3_000_000)
+    calculatedSum shouldBe expectedSum
+  }
+
+  it should "calculate the correct sum of all primes smaller than 11" in {
+    val expectedSum = BigInt("17")
+    val calculatedSum = Primes.sumOfPrimesBelow(11)
+    calculatedSum shouldBe expectedSum
+  }
+
+}