function showHide(id)
{
  el=document.getElementById(id).style;
  el.display=(el.display == 'block')?'none':'block';
}

function checkAll(f,el)
{
  for (var i=0;i<f.elements.length;i++)
  {
    var e=f.elements[i];
    if (e.name==el) e.checked=f.check_all.checked;
  }
}