摘要：
原题： Given a positive integer, output its complement number. The complement strategy is to flip the bits of its binary representation. Note: The given 阅读全文
摘要：
原题： Given an array of 2n integers, your task is to group these integers into n pairs of integer, say (a1, b1), (a2, b2), ..., (an, bn) which makes sum 阅读全文