Dsa
Binary Search Tree
Easy
Unique Values in BST
Given the root of a binary search tree (BST), return the number of unique values in the tree. A unique value is defined as a value that appears only once in the tree. You should implement your solution using a traversal method and storing values in a set.
Input format:
The input consists of several lines. The first line contains an integer n, the number of nodes in the tree. The next n lines each contain an integer that represents the value of the node in the BST. Assume that the input is given in level order (breadth-first traversal).
Output format:
Print a single integer: the number of unique values in the BST.
Example:
Input:
5
3
1
4
3
6
Output:
4
Key concepts
binary_search_treetraversalset
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