摘要：
Given an integer (signed 32 bits), write a function to check whether it is a power of 4. Example:Given num = 16, return true. Given num = 5, return fa 阅读全文
摘要：
Given an integer, write a function to determine if it is a power of three. Follow up:Could you do it without using any loop / recursion? Credits:Speci 阅读全文
摘要：
Given an integer, write a function to determine if it is a power of two. Example 1: Example 2: Example 3: 给一个整数，写一个函数来判断它是否为2的次方数。 利用计算机用的是二进制的特点，用位操作 阅读全文