第7周作业1-循环大战

import javax.swing.*;  
  
public class FactorialTest{  
    public static void main (String args[])  
    {      
        int n;    
        String s=(String)JOptionPane.showInputDialog(null,"请输入整数n","1到n的阶乘",      
                JOptionPane.PLAIN_MESSAGE,null,null,null);      
        n=Integer.parseInt(s);  
  
        {  
            long i,t,k;  
  
            for(i=1,t=1,k=1;t<=n;t++)  
            {  
                k*=t;  
            }  
            System.out.println(n+"!="+k);  
  
        }  
    }  
}