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Overall Editorial

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A - Signboard 1

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B - Set of Integers

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C - Sokoban

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D - Sum of (-1)^f(n)

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E - Sum of f(n)

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F - Stamps 1

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G - Stamps 2

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H - Stamps 3

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I - Stamps 4

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J - Sub-Post Correspondence Problem

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K - Set of Trees

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L - Signboard 2

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