HDU 2674:N！Again【数学】

N！Again

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 4304    Accepted Submission(s): 2284

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
   
   
   
   

 

Author

WhereIsHeroFrom

AC-code:

#include<cstdio>
int main()
{
	int ans;
	long long n;
	while(~scanf("%lld",&n))
	{
		if(n==0)
		{
			printf("1\n");
			continue;
		}
		ans=n%2009;
		while(n--)
		{
			if(n==0||ans==0)
				break;
			ans=(ans*(n%2009))%2009;
		}
		printf("%d\n",ans);
	}
	return 0;
}