How do i set a height on a div using javascript

Question

I have a div

div id='srch'

that has a computed height of 7000px how do i set the height of the another div to the same on window.load

div id='set_me'

Answer 1

document.getElementById('set_me').style.height = document.getElementById('srch').offsetHeight +'px';

if the possibility of the srch height will ever change, it will always match

Answer 2

document.getElementById('set_me').style.height = 
    document.getElementById('srch').offsetHeight + 'px';