摘要：A reversible prime in any number system is a prime whose "reverse" in that number system is also a prime. For example in the decimal system 73 is a re 阅读全文

摘要：With the 2010 FIFA World Cup running, football fans the world over were becoming increasingly excited as the best players from the best teams doing ba 阅读全文

摘要：The highest building in our city has only one elevator. A request list is made up with N positive numbers. The numbers denote at which floors the elev 阅读全文

摘要：Given a non-negative integer N, your task is to compute the sum of all the digits of N, and output every digit of the sum in English. Input Specificat 阅读全文