day 8 puzzle 1

src/day8/Node.scala

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+package day8
+
+class Node(val id: String, val nextNodes: Array[String]) {
+
+}

src/day8/Puzzle1.scala

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+package day8
+
+import scala.collection.mutable
+import scala.io.{BufferedSource, Source}
+import scala.util.matching.Regex
+import scala.util.matching.Regex.Match
+
+object Puzzle1 {
+  var rule: Array[Int] = Array.empty
+  val nodes: mutable.Map[String, Node] = new mutable.HashMap()
+  def loadInput(path: String): Unit = {
+    val source: BufferedSource = Source.fromFile(path)
+    val lines: String = source.getLines().mkString("\n")
+    val parts: Array[String] = lines.split("\n\n")
+
+    rule = parts(0).map(c => "LR".indexOf(c)).toArray
+    val regexp: Regex = new Regex("([A-Z]{3}) = \\(([A-Z]{3}), ([A-Z]{3})\\)")
+    for (line: String <- parts(1).split("\n")) {
+      val matches: Match = regexp.findFirstMatchIn(line).get
+      val id: String = matches.group(1)
+      val left: String = matches.group(2)
+      val right: String = matches.group(3)
+      nodes(id) = new Node(id, Array(left, right))
+    }
+
+    source.close()
+  }
+
+  def solve(path: String): Int = {
+    loadInput(path)
+
+    var solution: Int = 0
+    var id: String = "AAA"
+
+    while (id != "ZZZ") {
+      id = nodes(id).nextNodes(rule(solution % rule.length))
+      solution += 1
+    }
+
+    return solution
+  }
+
+  def main(args: Array[String]): Unit = {
+    val solution: Int = solve("./res/day8/input1.txt")
+    println(solution)
+  }
+}