function setHeight(){
//var left = document.getElementsByClassName('left');
//var container = document.getElementsByClassName('container');
//var mid = document.getElementsByClassName('mid');
//var right = document.getElementsByClassName('right');
//alert(document.documentElement.clientHeight);
var num = document.documentElement.scrollHeight +50;
document.getElementsByClassName("left")[0].style.height=num+'px';
document.getElementsByClassName("right")[0].style.height=num+'px';
document.getElementsByClassName("mid")[0].style.height=num+'px';
document.getElementsByClassName("container")[0].style.height=num+'px';

//right.style.height=container.style.height;
//mid.style.height=container.style.height;
}