N!Again
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 6338 Accepted Submission(s): 3325
Problem Description
WhereIsHeroFrom: Zty, what are you doing ?
Zty: I want to calculate N!......
WhereIsHeroFrom: So easy! How big N is ?
Zty: 1 <=N <=1000000000000000000000000000000000000000000000…
WhereIsHeroFrom: Oh! You must be crazy! Are you Fa Shao?
Zty: No. I haven's finished my saying. I just said I want to calculate N! mod 2009
Hint : 0! = 1, N! = N*(N-1)!
Input
Each line will contain one integer N(0 <= N<=10^9). Process to end of file.
Output
For each case, output N! mod 2009
Sample Input
4
5
Sample Output
24
120
类似这种数据级别大的不正常的阶乘,一定有特殊数据,试一下就能找到。
2009=7*7*41=49*41
也就是说,当n≥41时,n!一定是2009的倍数
#include <iostream> #include <stdio.h> using namespace std; int main() { long long n; while(scanf("%lld",&n)!=EOF){ ; ) cout<<<<endl; else{ ;i<=n;i++){ res=(res*i)%; } cout<<res<<endl; } } ; }