_Alexander的博客

题意： 一个数组无论顺序怎么改变，总满足(((????mod????1)mod????2)…mod????????−1)mod????????=(((????mod????????1)mod????????2)…mod????????????−1)mod???????????? 找这样数组的数量 如果一个数组都是d的倍数，那个这个数组无论咋改变顺序，mod出来的结果都是0 代码 typedef long long ll; using namespace std; const int MAXN=1e5+5

传送门 题意： Your task is to calculate the number of arrays such that: each array contains ???? elements; each element is an integer from 1 to ????; for each array, there is exactly one pair of equal elements; f...