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Topic
Puzzles
Logic riddles, number tricks, and stack-the-disks classics. Math, but disguised as fun.
Why puzzles matter
Every puzzle here teaches a different skill: pattern-spotting, careful counting, recursion, search strategies. They look easy. They aren't.
Magic squares
Place 1–9 so every row, column and diagonal sums the same.
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Tower of Hanoi
Move a stack one disk at a time without breaking the rule.
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Number guess
Binary-search a hidden number in 7 guesses.
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Pentominoes
Twelve shapes, one rectangle — fit them in.
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Königsberg bridges
Cross every bridge once — Euler proved you can't. See why.
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Logic riddles
Knights, knaves and lateral-thinking classics — work them out step by step.
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