勾股数列表（Find Pythagorean Triples）

//Find Pythagorean Triples within 500
//Java how to program, 5/e, Exercise 5.17
import javax.swing.*;
public class PythagoreanTriples {
    public static void main (String arg[])
   {
        boolean guard;
        int counter=1, number;
        String Number;
        Number=JOptionPane.showInputDialog("Enter the limit number:");
        number=Integer.parseInt(Number);
        JTextArea output=new JTextArea(17,20);
        JScrollPane scroller=new JScrollPane(output);
        output.setText("N1/t N2/tN3/t");
        for (int i=1;i<=number;i++)
            {for (int j=i+1;j<=number;j++)
                {for (int k=j+1;k<=number;k++)
                    {guard=i*i+j*j==k*k;
                    if (guard)
                        {output.append(i+"/t "+j+" /t"+k+" /t");
                    counter++;}
                    }
                }
            }
        output.append(" Total Pythagorean Triples number:"+counter);
        JOptionPane.showMessageDialog(null, scroller,"Pythagorean Triples",
                JOptionPane.INFORMATION_MESSAGE);
    }
}