Deduplicate 2023 day 17

sim642 · Dec 17, 2023 · 8e5a029 · 8e5a029
1 parent 61986c0
commit 8e5a029
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Showing 2 changed files with 41 additions and 48 deletions.
diff --git a/src/main/scala/eu/sim642/adventofcode2023/Day17.scala b/src/main/scala/eu/sim642/adventofcode2023/Day17.scala
@@ -3,62 +3,55 @@ package eu.sim642.adventofcode2023
 import eu.sim642.adventofcode2018.Day13.DirectionPos
 import eu.sim642.adventofcodelib.Grid
 import eu.sim642.adventofcodelib.GridImplicits.*
-import eu.sim642.adventofcodelib.graph.{BFS, Dijkstra, GraphSearch, GraphTraversal, UnitNeighbors}
+import eu.sim642.adventofcodelib.graph.*
 import eu.sim642.adventofcodelib.pos.Pos
 
 object Day17 {
 
   case class Crucible(pos: Pos, direction: Pos, directionCount: Int)
 
-  def leastHeatLoss(grid: Grid[Int]): Int = {
-
-    val graphSearch = new GraphSearch[Crucible] {
-      override val startNode: Crucible = Crucible(Pos.zero, Pos.zero, 0)
-
-      override def neighbors(crucible: Crucible): IterableOnce[(Crucible, Int)] = {
-        val Crucible(pos, direction, directionCount) = crucible
-        for {
-          offset <- Pos.axisOffsets
-          if offset != -direction
-          if !(directionCount == 3 && offset == direction)
-          newPos = pos + offset
-          if grid.containsPos(newPos)
-          newDirectionCount = if (offset == direction) directionCount + 1 else 1
-        } yield Crucible(newPos, offset, newDirectionCount) -> grid(newPos)
-      }
+  trait Part {
+    protected def canMove(crucible: Crucible, offset: Pos): Boolean
+    protected def canStop(crucible: Crucible): Boolean = true
 
-      private val targetPos = Pos(grid(0).size - 1, grid.size - 1)
+    def leastHeatLoss(grid: Grid[Int]): Int = {
 
-      override def isTargetNode(crucible: Crucible, dist: Int): Boolean = crucible.pos == targetPos
-    }
+      val graphSearch = new GraphSearch[Crucible] {
+        override val startNode: Crucible = Crucible(Pos.zero, Pos.zero, 0)
 
-    Dijkstra.search(graphSearch).target.get._2
-  }
+        override def neighbors(crucible: Crucible): IterableOnce[(Crucible, Int)] = {
+          val Crucible(pos, direction, directionCount) = crucible
+          for {
+            offset <- Pos.axisOffsets
+            if offset != -direction
+            if canMove(crucible, offset)
+            newPos = pos + offset
+            if grid.containsPos(newPos)
+            newDirectionCount = if (offset == direction) directionCount + 1 else 1
+          } yield Crucible(newPos, offset, newDirectionCount) -> grid(newPos)
+        }
+
+        private val targetPos = Pos(grid(0).size - 1, grid.size - 1)
 
-  // TODO: deduplicate
-  def leastHeatLossUltra(grid: Grid[Int]): Int = {
-
-    val graphSearch = new GraphSearch[Crucible] {
-      override val startNode: Crucible = Crucible(Pos.zero, Pos.zero, 0)
-
-      override def neighbors(crucible: Crucible): IterableOnce[(Crucible, Int)] = {
-        val Crucible(pos, direction, directionCount) = crucible
-        for {
-          offset <- Pos.axisOffsets
-          if offset != -direction
-          if direction == Pos.zero || (offset == direction && directionCount < 10) || (offset != direction && directionCount >= 4)
-          newPos = pos + offset
-          if grid.containsPos(newPos)
-          newDirectionCount = if (offset == direction) directionCount + 1 else 1
-        } yield Crucible(newPos, offset, newDirectionCount) -> grid(newPos)
+        override def isTargetNode(crucible: Crucible, dist: Int): Boolean = crucible.pos == targetPos && canStop(crucible)
       }
 
-      private val targetPos = Pos(grid(0).size - 1, grid.size - 1)
+      Dijkstra.search(graphSearch).target.get._2
+    }
+  }
+
+  object Part1 extends Part {
+    override protected def canMove(crucible: Crucible, offset: Pos): Boolean =
+      crucible.directionCount < 3 || offset != crucible.direction
+  }
 
-      override def isTargetNode(crucible: Crucible, dist: Int): Boolean = crucible.pos == targetPos && crucible.directionCount >= 4
+  object Part2 extends Part {
+    override protected def canMove(crucible: Crucible, offset: Pos): Boolean = {
+      val Crucible(pos, direction, directionCount) = crucible
+      direction == Pos.zero || (offset == direction && directionCount < 10) || (offset != direction && directionCount >= 4)
     }
 
-    Dijkstra.search(graphSearch).target.get._2
+    override protected def canStop(crucible: Crucible): Boolean = crucible.directionCount >= 4
   }
 
 
@@ -67,7 +60,7 @@ object Day17 {
   lazy val input: String = scala.io.Source.fromInputStream(getClass.getResourceAsStream("day17.txt")).mkString.trim
 
   def main(args: Array[String]): Unit = {
-    println(leastHeatLoss(parseGrid(input)))
-    println(leastHeatLossUltra(parseGrid(input)))
+    println(Part1.leastHeatLoss(parseGrid(input)))
+    println(Part2.leastHeatLoss(parseGrid(input)))
   }
 }
diff --git a/src/test/scala/eu/sim642/adventofcode2023/Day17Test.scala b/src/test/scala/eu/sim642/adventofcode2023/Day17Test.scala
@@ -28,19 +28,19 @@ class Day17Test extends AnyFunSuite {
       |999999999991""".stripMargin
 
   test("Part 1 examples") {
-    assert(leastHeatLoss(parseGrid(exampleInput)) == 102)
+    assert(Part1.leastHeatLoss(parseGrid(exampleInput)) == 102)
   }
 
   test("Part 1 input answer") {
-    assert(leastHeatLoss(parseGrid(input)) == 1110)
+    assert(Part1.leastHeatLoss(parseGrid(input)) == 1110)
   }
 
   test("Part 2 examples") {
-    assert(leastHeatLossUltra(parseGrid(exampleInput)) == 94)
-    assert(leastHeatLossUltra(parseGrid(exampleInput2)) == 71)
+    assert(Part2.leastHeatLoss(parseGrid(exampleInput)) == 94)
+    assert(Part2.leastHeatLoss(parseGrid(exampleInput2)) == 71)
   }
 
   test("Part 2 input answer") {
-    assert(leastHeatLossUltra(parseGrid(input)) == 1294)
+    assert(Part2.leastHeatLoss(parseGrid(input)) == 1294)
   }
 }