Dsa
Binary Search Tree
Medium
Inorder Successor in BST
In a binary search tree, the inorder successor of a node is the node with the smallest key greater than the node's key. Write a program that reads a BST and a specific node value, then finds and prints the inorder successor of that node. If the node has no inorder successor, print 'None'.
Input Format:
- The first line contains an integer N, the number of nodes in the BST.
- The next N lines each contain an integer representing the node value.
- The last line contains a single integer representing the target node value.
Output Format:
- Print the inorder successor value or 'None' if it does not exist.
Example:
Input:
5
20
10
30
5
15
10
Output:
15
Key concepts
binary_search_treeinorder_successorrecursion
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