L2Original starter · Free

Data structures and complexity

Part of the Technology & Software Engineering learning and recruiting path. Read the explanation and example, attempt the task, then open the self-check.

Understand

Arrays, maps, stacks, queues and trees suit different operations. Establish correctness before time/space complexity. Complexity describes scaling, not one machine timing.

Worked example

Pairwise duplicate checks take O(n²). A set usually gives expected O(n) traversal using extra space, subject to hashing behaviour.

Examples and numbers are educational, not employer questions, live market data or hiring criteria.

Practise and keep your output

Implement two duplicate-detection approaches with boundary cases, complexity and tradeoffs.

Keep inputs and sources, assumptions, steps, results and uncertainties in your own document. Attempt independently before checking below.

After attempting: answer and self-check

Distinguish worst-case from expected complexity; one benchmark does not prove universal superiority.

Official channels and further reading

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