// JavaScript Document

function Test()
 {
 var divHeight3 = ((document.getElementById('col3').offsetHeight) + 'px');
 var divHeight2 =((document.getElementById('col2').offsetHeight) + 'px');
  var divHeight1 =((document.getElementById('col1').offsetHeight) + 'px');
 if (divHeight3<=divHeight2){
    document.getElementById('col3').style.height = divHeight2;    
 }
  if (divHeight3<=divHeight1){
    document.getElementById('col3').style.height = divHeight1;    
 }
 }