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The ministers of the cabinet were quite upset by the message from the Chief of Security stating that they would all have to change the four-digit room 阅读全文
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Background Mr Somurolov, fabulous chess-gamer indeed, asserts that no one else but him can move knights from one position to another s... 阅读全文
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The GeoSurvComp geologic survey company is responsible for detecting underground oil deposits. GeoSurvComp works with one large rectangular region of 阅读全文
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There is a rectangular room, covered with square tiles. Each tile is colored either red or black. A man is standing on a black tile. F... 阅读全文
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There are n men ,every man has an ID(1..n).their ID is unique. Whose ID is i and i-1 are friends, Whose ID is i and i+1 are friends. These n men stand 阅读全文