closest_binary_search_tree_value_ii

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272. Closest Binary Search Tree Value II (Hard)

Related Topics

[Stack] [Tree]

Similar Questions

1. Binary Tree Inorder Traversal (Medium)
2. Closest Binary Search Tree Value (Easy)

Hints

Hint 1

Consider implement these two helper functions:

1. getPredecessor(N), which returns the next smaller node to N.
2. getSuccessor(N), which returns the next larger node to N.

Hint 2

Try to assume that each node has a parent pointer, it makes the problem much easier.

Hint 3

Without parent pointer we just need to keep track of the path from the root to the current node using a stack.

Hint 4

You would need two stacks to track the path in finding predecessor and successor node separately.