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 Details

    • Solution

      public Solution()
  • Method Details