Adding day 10

day10/bothparts.scala

@@ -0,0 +1,55 @@
+import scala.io.StdIn.readLine
+import scala.annotation.tailrec
+
+val MAX_X = 70
+val MAX_Y = 30
+
+case class Point(x: Int, y: Int, xv: Int, yv: Int) {
+  lazy val next: Point = Point(x + xv, y + yv, xv, yv)
+}
+
+object Point {
+  def apply(in: String): Point = 
+    "position=<((?:-|\\s)?\\d+), ((?:-|\\s)?\\d+)> velocity=<((?:-|\\s)?\\d+), ((?:-|\\s)?\\d+)".r.findFirstMatchIn(in).map {
+      m => Point(m.group(1).trim.toInt, m.group(2).trim.toInt, m.group(3).trim.toInt, m.group(4).trim.toInt)
+   }.get
+}
+
+def maxDistances(pts: List[Point]): (Int, Int) =
+  (pts.map(_.x).max - pts.map(_.x).min,
+   pts.map(_.y).max - pts.map(_.y).min)
+
+def movePoints(pts: List[Point]): List[Point] = pts.map(_.next)
+
+val points = Iterator
+  .continually(readLine)
+  .takeWhile(_ != null)
+  .map(Point.apply)
+  .toList
+
+@tailrec
+def iterateWhileUndrawable(pts: List[Point], it: Int): (List[Point], Int) = maxDistances(pts) match {
+  case (x, y) if x < MAX_X && y < MAX_Y => (pts, it)
+  case _ => iterateWhileUndrawable(movePoints(pts), it + 1)
+}
+
+def printPoints(pts: List[Point], size: ((Int, Int),(Int, Int))): Unit = 
+  (size._1._1 to size._1._2).foreach { y =>
+    (size._2._1 to size._2._2).foreach { x =>
+      if (pts.exists(p => p.x == x && p.y == y)) {
+        print("#")
+      } else {
+        print(".")
+      }
+    }
+    println("")
+ }
+
+val (drawablePoints, turns) = iterateWhileUndrawable(points, 0)
+
+val drawZone = (
+  (drawablePoints.map(_.y).min, drawablePoints.map(_.y).max),
+  (drawablePoints.map(_.x).min, drawablePoints.map(_.x).max))
+
+println(s"Visibility at ${turns}s")
+printPoints(drawablePoints, drawZone)