Given the root of a perfect binary tree, reverse the node values at each odd level of the tree.
[2,1,3,4,7,11,29,18], then it should become [18,29,11,7,4,3,1,2].Return the root of the reversed tree.
\n\nA binary tree is perfect if all parent nodes have two children and all leaves are on the same level.
\n\nThe level of a node is the number of edges along the path between it and the root node.
\n\n\n
Example 1:
\n![\"\"](\"https://assets.leetcode.com/uploads/2022/07/28/first_case1.png\")
\n\nInput: root = [2,3,5,8,13,21,34]\nOutput: [2,5,3,8,13,21,34]\nExplanation: \nThe tree has only one odd level.\nThe nodes at level 1 are 3, 5 respectively, which are reversed and become 5, 3.\n\n\n
Example 2:
\n![\"\"](\"https://assets.leetcode.com/uploads/2022/07/28/second_case3.png\")
\n\nInput: root = [7,13,11]\nOutput: [7,11,13]\nExplanation: \nThe nodes at level 1 are 13, 11, which are reversed and become 11, 13.\n\n\n
Example 3:
\n\n\nInput: root = [0,1,2,0,0,0,0,1,1,1,1,2,2,2,2]\nOutput: [0,2,1,0,0,0,0,2,2,2,2,1,1,1,1]\nExplanation: \nThe odd levels have non-zero values.\nThe nodes at level 1 were 1, 2, and are 2, 1 after the reversal.\nThe nodes at level 3 were 1, 1, 1, 1, 2, 2, 2, 2, and are 2, 2, 2, 2, 1, 1, 1, 1 after the reversal.\n\n\n
\n
Constraints:
\n\n[1, 214].0 <= Node.val <= 105root is a perfect binary tree.Compiled with clang 11 using the latest C++ 17 standard.
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