Given the root of a binary search tree with distinct values and a value val, return its depth: the number of edges from the root to the node holding val (the root has depth 0). Return -1 if val is not in the tree.
Examples
12
/ \
7 18
/ \ / \
3 9 15 22
\
5
Input: root = build_tree([12, 7, 18, 3, 9, 15, 22, None, 5]), val = 5
Output: 3
Input: root = build_tree([12, 7, 18, 3, 9, 15, 22, None, 5]), val = 10
Output: -1
Constraints
0 <= number of nodes <= 3000- All values are distinct integers
- O(h) time
Goals
- Count edges while searching
- Report a missing value with -1