How do you solve House Robber on a linear row of houses?
PICTURE THIS: HOW TO EXPLAIN IT
Simple meaning
dp[i] is the best of skipping i (dp[i-1]) or taking nums[i] plus dp[i-2].
WHY — DP instead of guessing?
Why interviewers care about DP:
question about DP.
trade-offs, and what you would actually do on a DSA project - not buzzwords.
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:
- 1dp[i] is the best
of skipping i (dp[i-1]) or taking nums[i] plus dp[i-2].
- 2Roll two variables for
O(n) time and O(1) space.
- 3Recursion without memo is
exponential because of overlapping skip/take branches.
- 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
dp[i] is the best of skipping i (dp[i-1]) or taking nums[i] plus dp[i-2]. Roll two variables for O(n) time and O(1) space.