摘要：Lucas定理是用来求 C(n,m) mod p，p为素数的值。（注意：p一定是素数） 给出组合数C(n,m), 表示从n个元素中选出m个元素的方案数。例如C(5,2) = 10, C(4,2) = 6.可是当n,m比较大的时候，C(n,m)很大！于是xiaobo希望你输出 C(n,m) mod p 阅读全文

摘要：知识点： 调和级数(即f(n))至今没有一个完全正确的公式，但欧拉给出过一个近似公式：(n很大时) f(n)≈ln(n)+C+1/2*n 欧拉常数值：C≈0.57721566490153286060651209 In mathematics, the nth harmonic number is t 阅读全文

摘要：用位图进行素数筛，节省空间。 阅读全文

摘要：Give a tree with n vertices,each edge has a length(positive integer less than 1001).Define dist(u,v)=The min distance between node u and v. Give an in 阅读全文

摘要：Loppinha loves to go to the gym with his friends. He takes his training sessions very seriously, and he always follows his schedule very strictly. He 阅读全文