g0101_0200.s0103_binary_tree_zigzag_level_order_traversal

Class Solution

java.lang.Object

g0101_0200.s0103_binary_tree_zigzag_level_order_traversal.Solution

public class Solution
extends Object

103 - Binary Tree Zigzag Level Order Traversal.

Medium

Given the root of a binary tree, return the zigzag level order traversal of its nodes’ values. (i.e., from left to right, then right to left for the next level and alternate between).

Example 1:

Input: root = [3,9,20,null,null,15,7]

Output: 3],[20,9],[15,7

Example 2:

Input: root = [1]

Output: 1

Example 3:

Input: root = []

Output: []

Constraints:

• The number of nodes in the tree is in the range [0, 2000].
• -100 <= Node.val <= 100

Constructor Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
List<List<Integer>>	zigzagLevelOrder(TreeNode root)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

zigzagLevelOrder

public List<List<Integer>> zigzagLevelOrder(TreeNode root)