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Consider an ordered set S of strings of N (1 <= N <= 31) bits. Bits, of course, are either 0 or 1. This set of strings is interesting because it is or 阅读全文
摘要：
The factorial of an integer N, written N!, is the product of all the integers from 1 through N inclusive. The factorial quickly becomes very large: 13 阅读全文
摘要：
The cows have developed a new interest in scanning the universe outside their farm with radiotelescopes. Recently, they noticed a very curious microwa 阅读全文