摘要：
Given a string S, check if the letters can be rearranged so that two characters that are adjacent to each other are not the same. If possible, output 阅读全文
摘要：
Given a positive integer n and you can do operations as follow: If n is even, replace n with n/2. If n is odd, you can replace n with either n + 1 or 阅读全文