Symmetric N-ary Tree

Given a N-ary tree, check whether it is symmetric around its root. N-ary tree is symmetric if value and shape look the same when reflected at the root.

Note - Nary-Tree input serialization is represented in their level order traversal, each group of children is separated by the null value 

Example1

Input: root = [5,null,3,5,3,null,10,null, 15, null, 10] 

Output: true

Example2

Input: root = [5,null,3,5,3,null,10,25, null, 15, null, 10] 

Output: false

Example3

Input: root = [5,null,3,5,3,null,10, null, 15, null, 25, 10]

Output: false

Example4

Input: root = [5,null,3,5,3,null,10,25, null, 15, null, 35, 10]

Output: false

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Intuition

Check each level, and check if its symmetric

Symmetric => Node val, and number of children at each end of level order should be the same