day 13 puzzle 1

src/day13/Puzzle1.scala

@@ -0,0 +1,92 @@
+package day13
+
+import scala.io.{BufferedSource, Source}
+
+object Puzzle1 {
+  var maps: Array[Array[Array[Boolean]]] = Array.empty
+  def loadInput(path: String): Unit = {
+    val source: BufferedSource = Source.fromFile(path)
+    val lines: String = source.getLines().mkString("\n")
+
+    val mapsStr: Array[String] = lines.split("\n\n")
+    maps = new Array(mapsStr.length)
+
+    for ((mapStr: String, i: Int) <- mapsStr.zipWithIndex) {
+      val rows: Array[String] = mapStr.split("\n")
+      val map: Array[Array[Boolean]] = new Array(rows.length)
+      for ((row: String, j: Int) <- rows.zipWithIndex) {
+        map(j) = row.map(_ == '#').toArray
+      }
+      maps(i) = map
+    }
+
+    source.close()
+  }
+
+  def getReflectionValue(map: Array[Array[Boolean]]): Int = {
+    val height: Int = map.length
+    val width: Int = if (height == 0) 0 else map(0).length
+    var value: Int = 0
+
+    for (x: Int <- 0 until width-1) {
+      if (isReflection(map, x)) {
+        value += x+1
+      }
+    }
+
+    val mapT: Array[Array[Boolean]] = transpose(map)
+
+    for (y: Int <- 0 until height-1) {
+      if (isReflection(mapT, y)) {
+        value += 100*(y+1)
+      }
+    }
+
+    return value
+  }
+
+  def isReflection(map: Array[Array[Boolean]], x: Int): Boolean = {
+    for (row: Array[Boolean] <- map) {
+      val a = row.dropRight(row.length - x - 1).reverse
+      val b = row.drop(x+1)
+      for (i: Int <- 0 until Math.min(a.length, b.length)) {
+        if (a(i) != b(i)) {
+          return false
+        }
+      }
+    }
+    return true
+  }
+
+  def transpose(map: Array[Array[Boolean]]): Array[Array[Boolean]] = {
+    val height: Int = map.length
+    val width: Int = if (height == 0) 0 else map(0).length
+
+    val mapT: Array[Array[Boolean]] = Array.ofDim(width, height)
+
+    for (y: Int <- 0 until height) {
+      for (x: Int <- 0 until width) {
+        mapT(x)(y) = map(y)(x)
+      }
+    }
+
+    return mapT
+  }
+
+  def solve(path: String): Int = {
+    loadInput(path)
+
+    var solution: Int = 0
+
+    for (map: Array[Array[Boolean]] <- maps) {
+      solution += getReflectionValue(map)
+    }
+
+    return solution
+  }
+
+  def main(args: Array[String]): Unit = {
+    val solution: Int = solve("./res/day13/input1.txt")
+    println(solution)
+  }
+}