Traversing a Binary Tree (Using a heuristic)

binary_tree_traversing.kt

// PROBLEM VISUALIZATION (https://i.imgur.com/cwg5LZ9.png)

val treeRowCount = 5

enum class Direction {
    ROOT,
    LEFT,
    RIGHT;
}

data class Node(val row: Int,
                val appliedDirection: Direction,
                val parent: Node? = null) {

    override fun toString() = generateSequence(this) { it.parent }
            .sortedBy { it.row }
            .map { "(row=${it.row},dir=${it.appliedDirection})" }
            .joinToString(" -> ")
}

fun traverse(node: Node, rightMovesLeft: Int) {

    var nextNode = node
    for (i in (node.row+1) until treeRowCount) {
        if (rightMovesLeft > 0)
            traverse(Node(i, Direction.RIGHT,nextNode), rightMovesLeft - 1)

        nextNode = Node(i,Direction.LEFT, nextNode)
    }
    println(nextNode)
}



fun main(args: Array<String>) {

    for (wave in 0..(treeRowCount-1)) {
        println("WAVE: $wave")
        traverse(Node(0,Direction.ROOT), wave)
    }
}