HDU 2674 N! Again

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
求N! MOD 2009的结果
我们这可这样想，如果在N！里找几个数乘的积等于2009就好了
结果我就弄了个循坏暴力了下，得知 2009＝7*7*41＝41*49；
也就是说当N>=49时N！ MOD 2009=0;
当N<49时我们就可以暴力了，水了吧。

LANGUAGE:C
CODE:
#include<stdio.h>
int main()
{
    int n;
    __int64 mul;
    while(scanf("%d",&n)!=EOF)
    {
        mul=1;
        if(n>=49)
        {
            printf("0\n");
            continue;
        }
        while(n>1)
        {
            mul*=n;
            mul%=2009;
            n--;
        }
        printf("%I64d\n",mul);
    }
    return 0;
}
作者：ultimater

补充：软件开发 , C++ ,