How do you collect the maximum cherries from two people walking a grid, or one person going to the end and back?
PICTURE THIS: FLEX VS GRID
Simple meaning
State is (row, col1, col2) for two walkers moving in sync toward the end
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:
- 1State is (row, col1,
col2) for two walkers moving in sync toward the end
- 2add the cell once
if they overlap.
- 33D DP is O(n^3)
for an n by n grid (or O(n^2 * m) analogously).
- 4Two independent max-paths overcount
cells visited twice.
- 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
State is (row, col1, col2) for two walkers moving in sync toward the end add the cell once if they overlap.