GATE CSE 2020 Q57: Comparisons to find the maximum in a min-heap of 1023 elements
- Programming and Data Structures
- 2 marks
- NAT
- No negative marking
Question
Consider the array representation of a binary min-heap containing 1023 elements. The minimum number of comparisons required to find the maximum in the heap is _______.
Try it: numerical answer: type the value
Numerical answer. No negative marking.
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Answer: 511 (official GATE 2020 final answer key)
Concept used: In a min-heap the maximum is always a leaf, and finding the maximum of values takes comparisons.
First step: A heap of 1023 nodes is a complete tree with 512 leaves; the maximum is among them.
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Source: official GATE 2020 CS question paper and final answer key, organised by IIT Delhi. Question paper · Answer key
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