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C - Digital Roots Description The digital root of a positive integer is found by summing the digits of the integer. If the resulting value is a single 阅读全文
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Catch That Cow Problem Description Farmer John has been informed of the location of a fugitive cow and wants to catch her immediately. He starts at a 阅读全文
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A - Switch Game Problem Description There are many lamps in a line. All of them are off at first. A series of operations are carried out on these lamp 阅读全文
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E - Just a Hook In the game of DotA, Pudge’s meat hook is actually the most horrible thing for most of the heroes. The hook is made up of several cons 阅读全文