摘要：
2017多校7 1010 找规律 列出前几项，斜着看，是杨辉三角 组合数 异或满足性质： $a \oplus b \oplus b = a$ 所以只需要关注组合数的奇偶性就可以了 规律是 对于$a_1$来说，那么$m$次变换在$a_n$上的异或次数为$C_{m+n 2}^{m 1}$ 对于$a_2$ 阅读全文
摘要：
UVA Live 7770 "题目链接" 真的是恶心到我了，怎么会有这么恶心的模拟题目呢，写了好几遍，一晚上就荒废了 C++ include include include include include include include include include include include 阅读全文