本文版权归ljh2000和博客园共有,欢迎转载,但须保留此声明,并给出原文链接,谢谢合作. 本文作者:ljh2000作者博客:http://www.cnblogs.com/ljh2000-jump/转载请注明出处,侵权必究,保留最终解释权!   Description To improve the organization of his farm, Farmer John labels each of his N (1 <= N <= 5,000) cows with a distinct s…

素数筛,数据范围不大,直接暴力筛. 坑:有个数据是 1 1,答案是1.差点没把我卡去世. 我的三观哪去了. #include<iostream> #include<cstdio> #include<utility> #include<algorithm> #include<cstring> using namespace std; const int maxp=2e4+5,maxn=5e3+5; int fac[maxp],a[maxn]; in…