What does Distinct do and what is the catch?
PICTURE THIS: HASH MAP
Simple meaning
It removes duplicates using default equality.
WHY — LINQ instead of guessing?
Why interviewers care about LINQ:
who only read docs from people who shipped.
and tied to .NET work.
Name the idea, why it exists, then one short example.
End with when you use it and one common pitfall.
STEPS — What happens step by step?
Before you speak the answer, walk the interviewer through these steps:
- 1It removes duplicates using
default equality.
- 2For objects I need
proper Equals/GetHashCode or a comparer.
- 3Order is not always
preserved the way beginners expect on all providers.
- 4Give an example
One tiny concrete case you can say aloud.
- 5Common mistake
What juniors usually get wrong.
- 6Close
When you pick this over the alternative.
EXAMPLE — See it in action
Here's a short line you can speak, broken into clear beats:
Note: Adapt this scaffold to your own project — keep it under 60–90 seconds.
Key takeaway
It removes duplicates using default equality. For objects I need proper Equals/GetHashCode or a comparer.