function numSort(a, b) {
  return a - b;
}

function setMaxHeight(elementIDs) {
	elementIDs = elementIDs.split(',');

	var elements = new Array();
	for(var i = 0; i < elementIDs.length; i++) elements[i] = document.getElementById(elementIDs[i]).offsetHeight;
	elements.sort(numSort).reverse();
	
	for(var i = 0; i < elementIDs.length; i++) document.getElementById(elementIDs[i]).style.height = elements[0] + "px";
}