styiannis/data-structures-js

import { ThreadedBinaryTreeDepthFirstIterator } from './ThreadedBinaryTreeDepthFirstIterator.js';

/**
 *
 * @param {ThreadedBinarySearchTreeNode} node
 * @return {ThreadedBinarySearchTreeNode}
 */
function lastSucessor(node) {
    while (node.hasRightChild()) {
        node = node.right;
    }

    return node;
}

/**
 * ThreadedBinaryTreeDepthFirstReverseIterator class.
 *
 * @extends {ThreadedBinaryTreeDepthFirstIterator}
 */
export class ThreadedBinaryTreeDepthFirstReverseIterator extends ThreadedBinaryTreeDepthFirstIterator {
    /**
     * Creates an instance of ThreadedBinaryTreeDepthFirstIterator.
     * 
     * @param {ThreadedBinarySearchTreeNode} node
     */
    constructor(node) {
        super(node, lastSucessor);
    }
    /**
     * Returns next element or throws TypeError in case this.current is null.
     *
     * @return {ThreadedBinarySearchTreeNode}
     */
    getNext() {
        let node = this.current;
        this.current = node.left;
        if (node.leftBit) {
            this.current = this.proceedNext(this.current);
        }
        return node;
    }
}