GATE CSE 2024 Session 2 Q39: What can be known about a BST from its set of keys alone
- Programming and Data Structures
- 2 marks
- MCQ
- −2/3 if wrong
Question
You are given a set of distinct integers. A binary search tree is created by inserting all elements of one by one, starting with an empty tree. The tree follows the convention that, at each node, all values stored in the left subtree of the node are smaller than the value stored at the node. You are not aware of the sequence in which these values were inserted into , and you do not have access to .
Which one of the following statements is TRUE?
Try it: multiple choice: exactly one correct option
Show answer and explanation
Answer: A (official GATE 2024 final answer key)
Concept used: The shape of a BST depends on insertion order, but its inorder traversal is always the sorted order.
First step: Insert the same set in two different orders and compare which traversals change.
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Source: official GATE 2024 Session 2 CS question paper and final answer key, organised by IISc Bangalore. Question paper · Answer key
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