function formattime(second) {
  var str="";

  if (second>=0) {
    s = second % 60;
    m = (second - s) / 60;
    if (s<10) {
      s="0"+s;
    }
    if (m<10) {
      m="0"+m;
    }
    str = m + ":" + s;
  }
  return str;
}

function enable_all(frm) {
  size=frm.elements.length;
  for (i=0; i<size; i++) {
    enable_ele(frm.elements[i]);
  }
}

function disable_all(frm) {
  size=frm.elements.length;
  for (i=0; i<size; i++) {
    disable_ele(frm.elements[i]);
  }
}

function disable_ele(ele) {
  ele.disabled = true;
}

function enable_ele(ele) {
  ele.disabled = false;
}