第7周作業1-循環大戰

import java.util.Scanner;

public class FactorialTest {
public static void main(String args[]){
	int n;
	Scanner y=new Scanner(System.in);
	n=y.nextInt( );
	int num=1;
	int i=1;
	do
	{
		num*=i;
		i++;
	}while(i<=n);
	System.out.print(num);
}
}