function sortNum(a,b) { return b-a}
function sameHeight(left,right,middle) {
		if (document.getElementById(left)) {
		var obj=new Array(3);
		var option=[left,right,middle];
		for(var i=0; i<option.length; i++) {
				document.getElementById(option[i]).style.height="auto";
				obj[i]=document.getElementById(option[i]).offsetHeight;
				nh=obj.sort(sortNum);
			}
		nh1=nh.splice(1,2);
		for(var i=0; i<option.length; i++) {
				document.getElementById(option[i]).style.height=nh+"px";
			}
	}
}

window.onload=function(){
	sameHeight('sidebar-left','sidebar-right','post-content');
	}