摘要：
Write an algorithm to determine if a number is "happy". A happy number is a number defined by the following process: Starting with any positive intege 阅读全文
摘要：
Given an absolute path for a file (Unix-style), simplify it. For example,path = "/home/", => "/home"path = "/a/./b/../../c/", => "/c" click to show co 阅读全文