BinaryTreeZigzagLevelOrderTraversal.cs

// Source : https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/description/ 
// Author : codeyu 
// Date : 2017年11月29日 18:03:45 

/**********************************************************************************
*
* Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then right to left for the next level and alternate between).
* 
* 
* For example:
* Given binary tree [3,9,20,null,null,15,7],
* 
* 3
* / \
* 9  20
* /  \
* 15   7
* 
* 
* 
* return its zigzag level order traversal as:
* 
* [
* [3],
* [20,9],
* [15,7]
* ]
* 
* 
*
**********************************************************************************/

using System;
using System.Collections.Generic;
using Algorithms.Utils;
namespace Algorithms
{
/**

 * Definition for a binary tree node.

 * public class TreeNode {

 *     public int val;

 *     public TreeNode left;

 *     public TreeNode right;

 *     public TreeNode(int x) { val = x; }

 * }

 */

public class Solution103 {

    public static IList<IList<int>> ZigzagLevelOrder(TreeNode root) {

        throw new NotImplementedException("TODO");

    }

}}