Adding day 18 p1 and 19 p1 + creating folder 2018

2018/day13/part1.scala

@@ -0,0 +1,197 @@
+import scala.io.StdIn.readLine
+import scala.annotation.tailrec
+
+val ESC = "\u001B"
+val RED = s"$ESC[1;31m"
+val BLU = s"$ESC[1;34m"
+val CLR = s"$ESC[0;37m"
+
+val CLEAR_SCREEN = s"$ESC[2J"
+
+case class Pos(x: Int, y: Int) {
+  def +(that: Pos): Pos = Pos(x + that.x, y + that.y)
+}
+
+object Up extends Pos(0, -1)
+object Down extends Pos(0, 1)
+object Left extends Pos(-1, 0)
+object Right extends Pos(1, 0)
+
+val directions: Array[Pos] = Array(
+  Left,
+  Up,
+  Right,
+  Down)
+
+sealed trait TrackOrientation {
+  val c: Char
+  def move(cart: Cart): Cart
+}
+
+trait Straight extends TrackOrientation {
+  override def move(cart: Cart): Cart =
+    cart.copy(p = cart.p + cart.o)
+}
+
+case object StraightImpl extends Straight {
+  override val c: Char = '?'
+}
+
+case object Horizontal extends Straight {
+  override val c: Char = '-'
+}
+case object Vertical extends Straight {
+  override val c: Char = '|'
+}
+
+case object Diag1 extends TrackOrientation {
+  override val c: Char = '/'
+  override def move(cart: Cart): Cart = cart.o match {
+    case Up => TurnRight.move(cart)
+    case Down => TurnRight.move(cart)
+    case Left => TurnLeft.move(cart)
+    case Right => TurnLeft.move(cart)
+  }
+}
+
+case object Diag2 extends TrackOrientation {
+  override val c: Char = '\\'
+  override def move(cart: Cart): Cart = cart.o match {
+    case Up => TurnLeft.move(cart)
+    case Down => TurnLeft.move(cart)
+    case Left => TurnRight.move(cart)
+    case Right => TurnRight.move(cart)
+  }
+}
+
+case object TurnLeft extends TrackOrientation {
+  override val c: Char = '?'
+
+  val changes: Map[Pos, Pos] = Map(
+    Up -> Left,
+    Down -> Right,
+    Left -> Down,
+    Right -> Up
+  )
+
+  override def move(cart: Cart): Cart = {
+    val newDir = changes(cart.o)
+    cart.copy(o = newDir, p = cart.p + newDir)
+  }
+}
+
+case object TurnRight extends TrackOrientation {
+  override val c: Char = '?'
+
+  val changes: Map[Pos, Pos] = Map(
+    Up -> Right,
+    Down -> Left,
+    Left -> Up,
+    Right -> Down
+  )
+
+  override def move(cart: Cart): Cart = {
+    val newDir = changes(cart.o)
+    cart.copy(o = newDir, p = cart.p + newDir)
+  }
+}
+
+val crossDirections = Array(
+  TurnLeft,
+  StraightImpl,
+  TurnRight)
+
+case object CX extends TrackOrientation {
+  override val c: Char = '+'
+
+  override def move(cart: Cart): Cart =
+    crossDirections(cart.nextCross)
+      .move(cart.copy(nextCross=(cart.nextCross + 1) % 3))
+}
+
+sealed trait Entry
+
+case class Track(p: Pos, o: TrackOrientation) extends Entry
+
+case class Cart(p: Pos, o: Pos, nextCross: Int = 0) extends Entry with Ordered[Cart] {
+  def compare(that: Cart): Int = {
+    val cmpL = p.y - that.p.y
+    if (cmpL == 0) {
+      p.x - that.p.x
+    } else {
+      cmpL
+    }
+  }
+
+  def next(tracks: Map[Pos, TrackOrientation]): Cart =
+    tracks(p).move(this)
+
+  override def toString: String = "#"
+}
+
+val input = Iterator
+  .continually(readLine)
+  .takeWhile(_ != null)
+  .toList
+  .zipWithIndex
+  .flatMap { case (l, y) => l.zipWithIndex.map { case (c, x) => Pos(x, y) -> c } }
+  .flatMap {
+    // tracks
+    case (p, c) if c == '|' => List(Track(p, Vertical))
+    case (p, c) if c == '-' => List(Track(p, Horizontal))
+    case (p, c) if c == '+' => List(Track(p, CX))
+    case (p, c) if c == '\\' => List(Track(p, Diag2))
+    case (p, c) if c == '/' => List(Track(p, Diag1))
+    case (p, c) if c == 'v' => List(Track(p, Vertical), Cart(p, Down))
+    case (p, c) if c == '^' => List(Track(p, Vertical), Cart(p, Up))
+    case (p, c) if c == '>' => List(Track(p, Horizontal), Cart(p, Right))
+    case (p, c) if c == '<' => List(Track(p, Horizontal), Cart(p, Left))
+    case _ => List()
+  }
+
+val tracks: Map[Pos, TrackOrientation] = input.flatMap {
+  case t: Track => Some(t.p -> t.o)
+  case _ => None
+}.toMap
+
+val initialCarts: List[Cart] = input.filter(_.isInstanceOf[Cart]).map(_.asInstanceOf[Cart])
+
+def printGame(tracks: Map[Pos, TrackOrientation], carts: List[Cart], turn: Int): Unit = {
+  val maxX = tracks.keys.map(_.x).max
+  val maxY = tracks.keys.map(_.y).max
+
+  // print(CLEAR_SCREEN)
+
+  val lines = (0 to maxY).map { y =>
+    val line = (0 to maxX).map { x =>
+      Pos(x, y) match {
+        case p if carts.exists(_.p == p) => 
+          carts.filter(_.p == p) match {
+            case cs if cs.size > 1 => s"${RED}X${CLR}"
+            case c :: Nil => s"${BLU}$c${CLR}"
+          }
+        case p if tracks.isDefinedAt(p) => tracks(p).c.toString
+        case _ => " "
+      }
+                              }.mkString("")
+                               "%03d %s".format(turn, line)
+                             }
+  lines.foreach(println)
+  // Thread.sleep(200)
+}
+
+@tailrec
+def playGame(tracks: Map[Pos, TrackOrientation])(carts: List[Cart], turn: Int): (Int, Pos) = {
+  val nextCarts = carts.sorted.map(_.next(tracks))
+  // printGame(tracks, nextCarts, turn)
+
+  (nextCarts ++ carts).groupBy(_.p).find(_._2.size > 1) match {
+    case Some((p, _)) => turn -> p
+    case _ => playGame(tracks)(nextCarts, turn + 1)
+  }
+}
+
+// printGame(tracks, initialCarts, 1)
+
+val (crashTurn, crashPos) = playGame(tracks)(initialCarts, 2)
+println(crashTurn, crashPos)