function doNext()
  {
    if(arrPages.length <= 1)
        return;
     var counter = arrPageIDs[curGUID];
    if(counter == arrPages.length - 1)
        this.document.location = arrPages[0];
    else
       this.document.location = arrPages[counter + 1];        
  }
  function doBack()
  {
    if(arrPages.length <= 1)
        return;
    var counter = arrPageIDs[curGUID];
    if(counter == 0)
        this.document.location = arrPages[arrPages.length - 1];
    else
       this.document.location = arrPages[counter - 1];     
  }      
 
  function getElement(str)
  {
    if(document.all)
       return document.all[str];
    if(document.getElementById)
       return document.getElementById(str);
    return null;  
  }

  function displayRandomInfoBoxes(n)
  {
     var arrRandNum = generateRandNum(n);
     var container = getElement("boxContainer");
     var box;
        
     for(var i = 0; i < arrRandNum.length; i++)
     {
        box = getElement("infoBox" + arrRandNum[i]);
        container.innerHTML = container.innerHTML + "<div>" + box.innerHTML + "</div>";        
     }
  }  

  function generateRandNum(n)
  {

    var arrOut = new Array();
        
    var num = (n < 4)? n : 4;

    var randNum = 0;
    for(var i = 0; i < num; i ++)
    {  
       randNum = (Math.floor(Math.random()* n)) + 1;       
       while(exist(arrOut,randNum))
       {
            randNum = (Math.floor(Math.random()* n)) + 1;
       }
       arrOut[arrOut.length] = randNum; 
    }    
    return arrOut;
 
 }  

  function exist(arr,elem)
  {
     var bOut = false;
     for(var i = 0; i < arr.length; i++)
     {
        if(arr[i] == elem)
            return true;
     }      
     return bOut;   
  }