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Description Businesses like to have memorable telephone numbers. One way to make a telephone number memorable is to have it spell a memorable word or 阅读全文
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Description Find and list all four-digit numbers in decimal notation that have the property that the sum of its four digits equals the sum of its digi 阅读全文
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Description A simple dartboard consists of a flat, circular piece of cork with concentric rings drawn on it. Darts are thrown at the board by players 阅读全文