June 2018 Update

Task/Langtons-ant/Kotlin/langtons-ant.kotlin

@@ -0,0 +1,34 @@
+// version 1.2.0
+
+enum class Direction { UP, RIGHT, DOWN, LEFT }
+
+const val WHITE = 0
+const val BLACK = 1
+
+fun main(args: Array<String>) {
+    val width = 75
+    val height = 52
+    val maxSteps = 12_000
+    var x = width / 2
+    var y = height / 2
+    val m = Array(height) { IntArray(width) }
+    var dir = Direction.UP
+    var i = 0
+    while (i < maxSteps && x in 0 until width && y in 0 until height) {
+        val turn = m[y][x] == BLACK
+        val index = (dir.ordinal + if (turn) 1 else -1) and 3
+        dir = Direction.values()[index]
+        m[y][x] = if (m[y][x] == BLACK) WHITE else BLACK
+        when (dir) {
+             Direction.UP    -> y--
+             Direction.RIGHT -> x--
+             Direction.DOWN  -> y++
+             Direction.LEFT  -> x++
+        }
+        i++
+    }
+    for (j in 0 until height) {
+        for (k in 0 until width) print(if(m[j][k] == WHITE) '.' else '#')
+        println()
+    }
+}