GateQA — Free GATE CS Previous Year Questions & Mock Tests

GateQA is a free GATE CS preparation platform with 3,500+ previous-year questions (1987–2026), 36,000+ aptitude questions, full-length year-wise mock tests, a built-in GATE calculator, performance analytics, and full offline support.

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GateQA — Free GATE CS Preparation Platform

GateQA is a free GATE CS preparation platform featuring 3,500+ previous-year questions (1987–2026), 36,000+ aptitude questions, subject-wise and year-wise mock tests, performance analytics, and full offline support. Practice Operating Systems, Algorithms, DBMS, Computer Networks, Theory of Computation, Discrete Mathematics, Compiler Design, Digital Logic, and more.

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Programming and DS

GATE CSE 2013 | Question: 43

Subject: Programming and DS
Paper: 2013
The preorder traversal sequence of a binary search tree is $30, 20, 10, 15, 25, 23, 39, 35, 42$. Which one of the following is the postorder traversal sequence of the same tree?
Answer: D

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