Jump Game
Each element is the maximum jump length from that index. Decide whether the last index is reachable from the first.
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Lesson notes
Try it before you watch
Restate the problem in your own words, list the edge cases, and sketch a solution with its running time. Then play the video and compare.
Reveal the key idea
Track the furthest index reachable so far. If the current index is ever beyond it, the end cannot be reached.
Pattern: Greedy & intervals. Make the locally best choice, usually after sorting, and argue why it never hurts later.
Complexity
| Measure | Bound |
|---|---|
| Time | O(n) |
| Extra space | O(1) |
Walkthroughs often start from a simpler approach first; aim to reach these bounds. New to Big-O? Read understanding algorithmic complexity.