阶乘--递归

class  JieCheng
{
	public static void main(String[] args) 
	{
		
          //System.out.println(jie(20));
		  JieCheng j = new JieCheng();
		  
		  System.out.println(j.jie(12));

	}

	public  long  jie(long n)
	{
	
	   if(n==0)//递归终止条件
		   return 1 ;
	   else
		   return n*jie(n-1);//递归循环体，需要抽取规律
	}


}