Dsa
Binary Search Tree
Hard
Kth Smallest Element in a BST
Write a function to find the kth smallest element in a binary search tree. The input consists of two lines; the first line contains the integer k, and the second line contains the values of the BST nodes in a format where 'x' represents a null node. The values are provided in the input line as space-separated integers. Print the kth smallest element. If k is out of bounds, print 'Invalid'. Example input/output format is below.
Input:
3
5 3 8 1 4 x x x x x 6
Output:
4
Key concepts
binary_search_treeinorder_traversalkth_smallest
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