dhown的博客

问题描述： Given an array of integers, every element appears twice except for one. Find that single one. Note: Your algorithm should have a linear runtime complexity. Could you implement it withou

问题描述：Calculate the sum of two integers a and b, but you are not allowed to use the operator + and -. 问题思路：加法可以拆解成两个步骤：不考虑进位，各位相加；各位计算进位与否。这个过程对十进制和二进制都满足。其中异或运算（半加运算）可实现第一步。第二步是与运算。 1. a和b只有做a