perfectnumber.java

完美数都能实现!显示1到1000的完美数,程序可以判断你输入的是不是!

import  java.awt.*;
import  javax.swing.*;
public class  PerfectNumber extends  JApplet 
{
	  JTextArea  outputArea=new JTextArea();
	  Container  container=getContentPane();
	  String  output;
		public void  init()
		{
		    long     num;
		    String   str;
		    str=JOptionPane.showInputDialog("please input the number until you input 0");
		    num=Integer.parseInt(str);
		    while(num!=0)
		    {
          Perfect(num);   		    
		      str=JOptionPane.showInputDialog("please input the number until you input 0"); 
		      num=Integer.parseInt(str);
	    	}
	    	//System.exit(0);
	    	
		    container.add(outputArea);	
		    outputArea.setText("1~~1000的完全数\n");
		    output="\t完数\t\t  因子\n";
		}	
		public  void  start()
		{
		    output+="\t"+1+"\t\t1\n";
		    for(int i=2;i<=1000;i++)
		    {
		       String  yy="\t";
		       int     sum=0;
		       for(int j=1;j<=i/2;j++)
		           if(i%j==0)
		           {   
		         	     yy+=j+",";
		         	     sum+=j;
		           }  
		       if(sum==i)
		          output=output+"\t"+i+"\t"+yy+"\n";
		    }  
		    outputArea.append(output);    
		    
		}
		
		public  void   Perfect(long num)
		{
			    long   sum=0;
			    if(num==1)
			     JOptionPane.showMessageDialog(null,num+"","1 is perfectnumber!",JOptionPane.INFORMATION_MESSAGE);
		    	else
		    	{
		    	for(int i=1;i<=num/2;i++)
		    	   if(num%i==0)
		    	      sum+=i;
		    	if(sum==num)
		    	   JOptionPane.showMessageDialog(null,num+"","the result is perfectnumber!",JOptionPane.INFORMATION_MESSAGE);
		    	   else
		    	   JOptionPane.showMessageDialog(null,num+"","the result is not perfectnumber!",JOptionPane.INFORMATION_MESSAGE);
	        }
	  }
}