HDU 1042 N!

N!

Problem Description

Given an integer N(0 ≤ N ≤ 10000), your task is to calculate N!

 

Input

One N in one line, process to the end of file.

 

Output

For each N, output N! in one line.

 

Sample Input

1 2 3

 

Sample Output

1 2 6

 

Author

JGShining（极光炫影）

解题思路：这题用Java大数，而且不能预处理，预处理会超内存

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