// JavaScript Document
var TimerLength = 720; //milliseconds
var DanceIntervalId = 0;
var ImagesInArray = 11;
var Arrow=new Array(11)
     Arrow[0]="a1";
     Arrow[1]="a2";
     Arrow[2]="a3";   
     Arrow[3]="a4";
     Arrow[4]="a5";
     Arrow[5]="a6";
     Arrow[6]="a7";
     Arrow[7]="a8";
     Arrow[8]="a9";
     Arrow[9]="a10";
     Arrow[10]="a11";

function Initialize ( )
{
var z = 0;
var e = document.getElementById(Arrow[z]);

   do {
	e = document.getElementById(Arrow[z]);
	if ( Math.random ( ) > .5 )
      {
        e.style.display = 'block';
      }
      else
      {
        e.style.display = 'none';
      }
      z++;
   }
   while (z < ImagesInArray);
   DanceIntervalId = setInterval ( "toggleImage()", TimerLength );
}

function DanceClickHandler ( )
{
  if ( document.getElementById("DanceButton").value == "Click me!" )
  {
    // Start the timer
    document.getElementById("DanceButton").value = "Enough already!";
    DanceIntervalId = setInterval ( "toggleImage()", TimerLength );
  }
  else
  {
    document.getElementById("DanceButton").value = "Click me!"; //reset button
    clearInterval ( DanceIntervalId );//clear the interval timer
  }
}

function get_random()
{
    var ranNum= Math.floor(Math.random()*ImagesInArray);
    return ranNum;
}

function toggle(Q)
{
    var e = document.getElementById(Arrow[Q]);
    if (e.style.display == 'none')
    	e.style.display = 'block';
    else
      e.style.display = 'none';
}

function toggleImage()
{
	if ( Math.random ( ) > .5 )
      {
        var x=get_random(); 
	  var its = toggle(x);
      }
      else
      {
        var x=get_random(); 
	  var its = toggle(x);
	  x=get_random();
        its=toggle(x);
      }
// End
}