The Puzzle Gauntlet
The Puzzle Gauntlet 🏟️
This is it — the graduation unit. No new tools. No training wheels. Just puzzles.
Here's a secret worth knowing: many of these problems are FAMOUS. Two Sum, the palindrome check, the anagram test, the majority vote, move-the-zeros, Collatz, Fibonacci — grown-up programmers get asked these in job interviews at the biggest tech companies in the world. You're about to solve them for fun, in a costume party version.
How to fight in the gauntlet
- Read twice, code once. What exactly comes in? What exactly goes out?
- Name the pattern. Almost everything here is secretly a search, a tally, a best-so-far, a pair-hunt, a stack trick, or a simulation. Once you name it, you've half solved it.
- Brute force with pride, then upgrade. Several puzzles appear twice — the honest slow way, then a TURBO version with a clever trick. Slow-but-correct is always a respectable first draft; the upgrade is where the magic lives. Two Sum's dict trick is the single most useful idea in this whole unit — savor it.
- Test your instincts against the edges. Negative numbers, ties, empty-ish inputs — the gauntlet hides its traps where instincts fail and tests don't.
Between you and graduation stand Pairs & Partners, Words & Mirrors, Number Puzzles, and the Grand Challenges — where every problem needs at least two of your skills at once.
And at the very top of the Champion path waits the Final Door, with a three-part lock. You've been collecting its keys since your very first print(). Go. 🎓
# problems
1Two Sum, Turbo Mode
Challenge
2The Boat for Two
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3The Power Duo
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4Almost a Mirror
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5Find the Twins in Class
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6Switch the Singing Letters
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7The Odometer Rolls
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8The Prime Guest List
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9The Number Mirror
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10The Tournament Bracket
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11The Treasure Map Decoder
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12The School Fair Report
Challenge
13The Emoji Stack Machine
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14The Snack Machine
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15The Leaderboard Insert
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16The Lost Library Book
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17Streak Keeper of Every Team
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18The Amusement Park Day
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19The Final Door
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