beginner
10 min read
Integer to Roman
The code is short. The trap is assuming the rules are short enough for a pile of special cases.
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Greedy Techniques
Make provably safe local choices that lead to a globally optimal result.
Problems
Problems in Greedy Techniques
Practice problems that share this primary solution pattern and compare the clues that reveal it.
intermediate
10 min read
Jump Game
The wrong mental model is a tree of jump paths. The useful model is a moving boundary: the farthest index reachable by any valid path found so far.
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intermediate
11 min read
Jump Game II
The common mistake in a Jump Game II solution is to commit too early: “From this index, which landing position should I choose?” That creates a path-search…
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