一天一个小知识(位运算之异或)
给定数n,是否存在(a^b+a^c+b^c==n) 当n为偶数时,a=0,b=n/2,c=n/2满足 当n为奇数时,不存在 https://blog.csdn.net/weixin_43918473/article/details/125708076 https://codeforces.com/contest/1699/problem/A