(Kotlin) day 13 part 1 done

13/Cart.kt

@@ -21,7 +21,7 @@ public class Train {
     fun crossIntersection() {
         when (this.nextTurn) {
             Turn.LEFT -> {
-                this.direction -= this.nextTurn.dir
+                this.direction += this.nextTurn.dir
                 this.nextTurn = Turn.STRAIGHT
             }
             Turn.STRAIGHT -> {
@@ -39,7 +39,7 @@ public class Train {
         if (this.direction < 0) {
             this.direction = (this.direction + 4)
         } else if (this.direction > 3) {
-            this.direction = (this.direction + 1) % 4
+            this.direction = (this.direction) % 4
         }
     }
 }
@@ -48,7 +48,7 @@ public class Train {
 public enum class Turn(val dir: Int) {
     LEFT(-1),
     STRAIGHT(0),
-    RIGHT(-1)
+    RIGHT(1)
 }
 
 public enum class Field() {

13/main.kt

@@ -24,6 +24,14 @@ class Main() {
         }
     }
 
+    fun findCrash(trains: MutableList<Train>) {
+        var positions = HashSet<Pair<Int, Int>>(trains.size - 1)
+        trains.map{ t -> Pair(t.x, t.y) }.forEach{ p ->
+            if (!(p in positions)) { positions.add(p); println("adding $p") }
+            else { println(p) }
+        }
+    }
+
     fun parseTrain(c: Char, x: Int, y: Int): Train {
         val dir = when (c) {
             '^' -> 0
@@ -43,13 +51,13 @@ class Main() {
             3 -> t.x -= 1
             else -> throw IllegalArgumentException("this shouldn’t happen either selphyDerp")
         }
-        println("x ${t.x}, y ${t.y}")
-        val current = field[t.x][t.y]
-        println(current)
+        //println("x ${t.x}, y ${t.y}")
+        val current = field[t.y][t.x]
+        //println(current)
         when (current) {
             Field.VERTICAL, Field.HORIZONTAL -> {}
-            Field.TOP_LEFT -> t.direction = t.direction xor 1
-            Field.TOP_RIGHT -> t.direction = t.direction xor 3
+            Field.TOP_LEFT -> {println("hit $current, changing dir from ${t.direction} to ${t.direction xor 1}"); t.direction = t.direction xor 1}
+            Field.TOP_RIGHT -> {println("hit $current, changing dir from ${t.direction} to ${t.direction xor 3}"); t.direction = t.direction xor 3}
             Field.INTERSECTION -> t.crossIntersection()
             Field.EMPTY -> throw IllegalStateException("I shouldn’t be here")
         }
@@ -69,7 +77,7 @@ class Main() {
             for ((x, char) in line.toCharArray().withIndex()) {
                 if (char in TRAINS) {
                     val newTrain = parseTrain(char, x, y)
-                    println(newTrain)
+                    println("train at $x, $y")
                     println(char)
                     trains.add(newTrain)
                 }
@@ -79,12 +87,18 @@ class Main() {
         }
         var positions = HashSet<Pair<Int, Int>>(trains.size)
         positions.addAll(trains.map{ t -> Pair(t.x, t.y) })
+        //println(field[75])
+        var current = 0
         while (positions.size == trains.size) {
-            trains.forEach{ t -> moveTrain(t) }
+            trains[current] = moveTrain(trains[current])
+            //trains.forEach{ t -> moveTrain(t) }
+            //val pos = Pair(trains[15].y, trains[15].x)
+            //println("$pos: ${field[pos.first][pos.second]}: ${trains[15].direction}")
             positions.clear()
             positions.addAll(trains.map{ t -> Pair(t.x, t.y) })
+            current = (current + 1) % trains.size
         }
-        println(trains)
+        findCrash(trains)
     }
     }
 }