//MathDemo.java
//demo of Math class

import javax.swing.*;

public class MathDemo extends JApplet {

    public static void main(String[] argv) {
    //public void init () {//uncomment this and comment out above main for applet

	String  input;
	int loops;
	double favNum, favNumSqrt, circumference, area;

	JOptionPane.showMessageDialog(null, "Here's Math.PI: " + Math.PI);

	input = JOptionPane.showInputDialog("Enter your favorite number");
	favNum = Double.parseDouble(input);

	circumference = 2 * Math.PI * favNum;
	area = Math.PI * favNum * favNum;
	JOptionPane.showMessageDialog(null, 
	    "Circumference of circle of radius " + 
	    favNum + " = " + circumference + 
	    "\nArea of circle = " + area);

	favNumSqrt = Math.sqrt(favNum);
	JOptionPane.showMessageDialog(null, 
	    "Here's square root of your favorite number: " + favNumSqrt);

	input = JOptionPane.showInputDialog("Enter number of times to loop");
	loops = Integer.parseInt(input);
	for (int i=0; i<loops; i++)
	    JOptionPane.showMessageDialog(null, "Here's a random number: " + 
					   Math.random());

	//random int between 0 and N-1 
	JOptionPane.showMessageDialog(null,"Random integer between 0 and " +
				      favNum + ": " +
				      (int)(Math.random()*favNum));
    }
}