var BannerArray;
var DirName;
var g;

function FillArray(filename, numfiles)
{   
        var y;
        
        DirName = filename;
        BannerArray = new Array(numfiles);
        
        for (var x = 1; x <= numfiles; x++)
        {
            if (x < 10)
            {
                y = '0' + x;
            } else
            {
                y = x;
            }
            BannerArray[x-1] = filename + '_' + y + '.jpg';
        }   
                
}

function AddHPBanner(ii, z)
{    
    if (!z) var z = 0;
    
    if (z != 0) 
    {
        switch(z)
        {
			case 1:
		        g = GetPrevious(ii); 
		        document.getElementById('HomepageBannerIMG').src='/ncee/pubs/20084012/ppt/' + DirName + '/' + BannerArray[g];			
			    break;
			case 2:
		        g = GetNext(ii); 
		        document.getElementById('HomepageBannerIMG').src='/ncee/pubs/20084012/ppt/' + DirName + '/' + BannerArray[g];
			    break;
            default:
                break;			    
            
        }
    } else
    {
        
	    if (ii==null)
	    {
		    g = 0; 
		    ii = 0;
		    document.write('<IMG src="/ncee/pubs/20084012/ppt/' + DirName + '/' + BannerArray[g] + '" alt="' + BannerArray[g] + '" id="HomepageBannerIMG" width="462" height="347" border="0">');
	    }
    }	
    
}

function GetNext(x)
{
    if (x >= BannerArray.length - 1) 
    {
        return 0;        
    }        
    else
    {
       return x + 1;
    }
}

function GetPrevious(x)
{
    if (x == 0) 
    {
        return BannerArray.length - 1;        
    }        
    else
    {
       return x - 1;
    }
}