How do you find the minimum number of jumps to reach the last index?
PICTURE THIS: ARRAY IN MEMORY
Index starts at 0. Scan once for max — O(n).
Simple meaning
Greedy BFS-on-array: while in the current jump range, track the farthest you can reach, then increment jumps when the range ends.
WHY — Greedy instead of guessing?
Why interviewers care about Greedy:
question about Greedy.
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:
- 1Greedy BFS-on-array: while in
the current jump range, track the farthest you can reach, then increment jumps when the range ends.
- 2Time is O(n) and
space is O(1).
- 3How it works
DP min-jumps is O(n^2).
- 4If farthest ever stalls
before the end, it is unreachable.
- 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
Greedy BFS-on-array: while in the current jump range, track the farthest you can reach, then increment jumps when the range ends. Time is O(n) and space is O(1).