Given a root node reference of a BST and a key, delete the node with the given key in the BST. Return the root node reference (possibly updated) of the BST.
Basically, the deletion can be divided into two stages:
Search for a node to remove.
If the node is found, delete the node.
Follow up: Can you solve it with time complexity O(height of tree)?
Input: root = [5,3,6,2,4,null,7], key = 3
Explanation: Given key to delete is 3. So we find the node with value 3 and delete it.
One valid answer is [5,4,6,2,null,null,7], shown in the above BST.
Please notice that another valid answer is [5,2,6,null,4,null,7] and it's also accepted.
Input: root = [5,3,6,2,4,null,7], key = 0
Explanation: The tree does not contain a node with value = 0.
Input: root = , key = 0
The number of nodes in the tree is in the range [0, 104].