qq_41049928的博客

Chiaki has a very big sheet of paper. This sheet has a form of rectangle with dimensions 1 x n and numbers from 1 to n was written on each small 1 x 1 grid. Chiaki would like to fold the paper using t...

题意：一个序列，q次询问，每次问你某个指定区间内的EXtreme XOR值。一个长度为l的区间的EXtreme XOR值被定义为，从左到右，将每相邻的两个数XOR起来，产生l-1个新的值，……如此循环，总共l-1次，直到剩下一个值。问的就是这个值是多少。一个区间的答案，只和每个数被异或的次数的奇偶性有关,而这个被异或的次数恰好是二项展开式的系数,手写观察下。然后预处理每个长度奇数的位置...