- 1
Commit and Never Look Back
Greedy commits to the locally best choice with zero undo — safe exactly when an exchange argument holds.
Multiple choice - 2
Assign Cookies
Sort children and cookies, then give each child the SMALLEST cookie that satisfies them — greedy's classic exchange argument.
Complete codeMultiple choiceTrace - 3
Lemonade Change
Count your $5s and $10s; for a $20, spend the less flexible $10 first — versatile bills are worth hoarding.
Complete codeDebugMultiple choiceTrace - 4
Stock Trading, Greedily
Sum every positive day-to-day rise — any profitable multi-day hold telescopes into exactly those rises, so grabbing each one is provably optimal.
Complete codeMultiple choiceTrace - 5
Jump Game
One sweep, one number: the furthest reachable index. Extend it at every reachable position, and dead-stop the moment i outruns it.
Complete codeDebugMultiple choiceTrace - 6
Partition Labels
Map each letter to its last occurrence, sweep while extending end = max(end, last[c]), and cut the instant i == end — the earliest legal cut is always safe.
Complete codeDebugMultiple choiceTrace - 7
Greedy CheckpointCheckpoint
No new concepts — transfer the island's greedy moves to unseen problems: pairing boat passengers, loading a truck by value, splitting people across two cities, and counting wiggle direction flips.
Code orderMultiple choiceTrace - 8
Greedy ReviewReview
Mixed recap of the island: the exchange argument as greedy's proof obligation, sort-first setup, greedy vs backtracking vs DP, the coin counterexample, one-pass state sweeps, and sort-dominated cost vs exponential search.
Complete codeMultiple choice - 9
Boss: Gas StationBoss
The island's final test: circle the stations once. Total net fuel decides solvability; one pass with a restarting tank finds the unique start — and the boss's trap is restarting at the failed station instead of after it.
Complete codeDebugCode orderMultiple choiceTrace
Backtracking & Greedy is part of AlgoFox Pro
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