Create part2.scala

day12/part2.scala

@@ -0,0 +1,53 @@
+import scala.io.Source
+import scala.collection.mutable.Queue
+import scala.collection.mutable.HashMap
+
+object PartTwo {
+    def pathfind(map: List[List[Int]], width: Int, length: Int, end: (Int, Int)): Int = {
+        var open = Queue(end)
+        var closed = HashMap.empty[(Int, Int), Int]
+        closed += (end -> 0)
+        while (!open.isEmpty) {
+            var node = open.dequeue()
+            if (map(node._2)(node._1) == 97) { return closed(node) }
+            for ((dx, dy) <- List((1, 0), (0, 1), (-1, 0), (0, -1))) {
+                var newnode = (node._1 + dx, node._2 + dy)
+                if ((newnode._1 < length) && (newnode._2 <= width) && (newnode._1 >= 0) && (newnode._2 >= 0) && (!closed.contains((newnode._1, newnode._2)))) {
+                    if ((map(newnode._2)(newnode._1) + 1 >= map(node._2)(node._1))) {
+                        open.enqueue((newnode._1, newnode._2))
+                        closed += ((newnode._1, newnode._2) -> (closed(node) + 1))
+                    }
+                }
+            }
+        }; -1
+    }
+
+    def main(args: Array[String]) = {
+        val fp: Source = Source.fromFile("input.txt")
+
+        var end: (Int, Int) = (0, 0) 
+        var width, length: Int = 0
+        var line: List[Int] = List()
+        var map: List[List[Int]] = List()
+        while (fp.hasNext) {
+            var c: Char = fp.next()
+            if (c == '\n') {
+                map = map :+ line
+                line = List()
+                width += 1
+                length = 0
+
+            } else {
+                if (c == 'E') { 
+                    end = (length, width)
+                    line = line :+ 122
+                } else if (c == 'S') { line = line :+ 97 }
+                else { line = line :+ c.toByte }
+                length += 1
+            }
+        }
+        fp.close()
+
+        println(pathfind(map :+ line, width, length, end))
+    }
+}