Given the
Example 1:
Input: root = [1,2,2,3,4,4,3]
Output: true
Example 2:
Input: root = [1,2,2,null,3,null,3]
Output: false
Constraints:
The number of nodes in the tree is in the range
root of a binary tree, check whether it is a mirror of itself (i.e., symmetric around its center).
Example 1:
Input: root = [1,2,2,3,4,4,3]
Output: true
Example 2:
Input: root = [1,2,2,null,3,null,3]
Output: false
Constraints:
The number of nodes in the tree is in the range
[1, 1000].
-100 <= Node.val <= 100
If a tree is a perfect mirror image of itself, how do the outer edges (the leftmost and rightmost nodes) relate to each other?
Could you solve it both recursively and iteratively?