import java.io.*;
import java.util.*;
import java.math.*;
public class Main {
       public static void main(String args[])
       {
    	   Scanner cin=new Scanner(System.in);
    	   int n;
    	   BigInteger s;
    	   while(cin.hasNextInt())
    	   {
    		   s=BigInteger.valueOf(1);
    		   n=cin.nextInt();
    		   for(int i=2;i<=n;i++)
    		   {
    			   s=s.multiply(BigInteger.valueOf(i));
    		   }
    		   System.out.println(s);
    	   }
       }
}

  

posted on 2011-09-23 16:34  枫叶飘泪  阅读(219)  评论(0编辑  收藏  举报