Skip to content
Sharp

Core Collections · interview question

A bug appears around sets. What is the strongest first debugging move?

Multiple choiceMediumchapter-3-curatedpremiumcore-collectionssets
python
seen_skus = {"SKU-1", "SKU-2"}
seen_skus.add("SKU-3")
print("SKU-2" in seen_skus)
Choose one answer
Answer and explanation

Correct answer

C. Trace one concrete example, inspect the state transitions, and compare them to the intended rule before rewriting anything.

Why

That approach is reliable because it creates evidence. Using a list for repeated membership checks adds unnecessary work and often obscures the intent.

Test yourself on Core Collections

A free test with instant, explained results. No account needed.

Start free test

More Core Collections questions

All Core Collections questions →