摘要：
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 of 阅读全文
摘要：
The Hamming distance between two integers is the number of positions at which the corresponding bits are different. Given two integers x and y, calcul 阅读全文