// http://www.onlinetools.org/articles/unobtrusivejavascript/chapter4.html
function addEvent(obj, evType, fn){ 
 if (obj.addEventListener){ 
   obj.addEventListener(evType, fn, true); 
   return true; 
 } else if (obj.attachEvent){ 
   var r = obj.attachEvent("on"+evType, fn); 
   return r; 
 } else { 
   return false; 
 } 
}

function recompute() {
  e = document.getElementById('celkem').firstChild;
  s = 0;
  s += parseInt (document.getElementById('b5000').value) * 26;
  s += parseInt (document.getElementById('b2000').value) * 28;
  s += parseInt (document.getElementById('b1000').value) * 38;
  s += parseInt (document.getElementById('b500').value) * 45;
  s += parseInt (document.getElementById('b200').value) * 15;
  s += parseInt (document.getElementById('b100').value) * 10;
  s += parseInt (document.getElementById('b50').value) * 8;
  s += parseInt (document.getElementById('m50').value) * 14;
  s += parseInt (document.getElementById('m20').value) * 12;
  s += parseInt (document.getElementById('m10').value) * 110;
  s += parseInt (document.getElementById('m5').value) * 110;
  s += parseInt (document.getElementById('m2').value) * 150;
  s += parseInt (document.getElementById('m1').value) * 750;
  s += parseInt (document.getElementById('m6').value) * 140;
  s += parseInt (document.getElementById('m7').value) * 150;
  s += parseInt (document.getElementById('m8').value) * 90;
  s += parseInt (document.getElementById('m9').value) * 90;
  s += parseInt (document.getElementById('m11').value) * 140;
  s += parseInt (document.getElementById('m12').value) * 150;
  s += parseInt (document.getElementById('m13').value) * 200;
  s += parseInt (document.getElementById('m14').value) * 200;
  s += eval (document.getElementById('eval').value);
  e.data = s;
}

function addEvents() {
  inputs = document.getElementsByTagName('input');
  for (i=0;i<inputs.length;i++) {
    x = addEvent (inputs[i], 'change', recompute);
  }
}
addEvent (window, 'load', addEvents);
addEvent (window, 'load', recompute);