var tmpid,am,let,count;
function tree(letter, amount)
{
	count=1;
    am=amount;
    let=letter;
    show2();
}

function show2()
{
	if(count<am)
    {
      tmpid=let + count;
      setTimeout('show(tmpid, 1)', 20);
      count++;
    } else
    {
      tmpid=let + count;
      setTimeout('show(tmpid, 0)', 20);
    }
}

function show(id, flag)
{
    var el = document.getElementById(id);
    el.style.display = (el.style.display == 'block')?'none':'block';
    if(flag!=0) show2();
}