GATE DA 2024 Set 1 — Question 28

MSQ+1 / -0MediumBinary Tree TraversalsTreesProgramming, Data Structures & Algorithms

Programming, Data Structures & Algorithms → Trees → Binary Tree Traversals

Last updated 5 September 2026

Question

Consider the following tree traversals on a full binary tree: (i) Preorder (ii) Inorder (iii) Postorder Which of the following traversal options is/are sufficient to uniquely reconstruct the full binary tree?

Correct answer (A) (i) and (ii); (B) (ii) and (iii); (C) (i) and (iii) Solution To uniquely reconstruct a binary tree, Inorder traversal combined with either Preorder or Postorder traversal is sufficient. Thus, options (A) and (B) are correct for any binary tree. For a full binary tree (a tree where every node has either 0 or 2 children), the combination of Preorder and Postorder traversals is also sufficient to uniquely reconstruct the tree. This is a specific property of full binary trees. Therefore, options (A), (B), and (C) are all sufficient. Turn this into a strength. Explore AI-powered practice and doubt support with Success Tracker.

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Correct answer (A) (i) and (ii); (B) (ii) and (iii); (C) (i) and (iii) Solution To uniquely reconstruct a binary tree, Inorder traversal combined with either Preorder or Postorder traversal is sufficient. Thus, options (A) and (B) are correct for any binary tree. For a full binary tree (a tree where every node has either 0 or 2 children), the combination of Preorder and Postorder traversals is also sufficient to uniquely reconstruct the tree. This is a specific property of full binary trees. Therefore, options (A), (B), and (C) are all sufficient.

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