GATE CSE 2020 Q26: Worst-case time to build a sorted linked list by n insertions
- Programming and Data Structures
- 1 mark
- MCQ
- −1/3 if wrong
Question
What is the worst case time complexity of inserting elements into an empty linked list, if the linked list needs to be maintained in sorted order?
Try it: multiple choice: exactly one correct option
Wrong answer costs 1/3 mark in GATE.
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Answer: C (official GATE 2020 final answer key)
Concept used: Finding the insertion point in a linked list is a linear scan; binary search is not possible.
First step: The -th insertion may scan all existing nodes; sum this over to .
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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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