How do you maximize coins from bursting balloons?
PICTURE THIS: HOW TO EXPLAIN IT
Simple meaning
Interval DP over the last balloon burst in a range: dp[l][r] = max over k of nums[l]*nums[k]*nums[r] + dp[l][k] + dp[k][r], after padding 1s.
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:
- 1Interval DP over the
last balloon burst in a range: dp[l][r] = max over k of nums[l]*nums[k]*nums[r] + dp[l][k] + dp[k][r], after padding 1s.
- 2Time is O(n^3) and
space is O(n^2).
- 3Greedy bursting smallest first
is not optimal.
- 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
Interval DP over the last balloon burst in a range: dp[l][r] = max over k of nums[l]*nums[k]*nums[r] + dp[l][k] + dp[k][r], after padding 1s. Time is O(n^3) and space is O(n^2).