for my different elements i have the same class tag with only different ending. My html elements;

id="inner-main-container-one"
id="inner-main-container-two"
id="inner-main-container-three"

My code define in js is:

var content = document.getElementByID('inner-main-container-one');
var contentone = document.getElementByID('inner-main-container-two');
var contenttwo = document.getElementByID('inner-main-container-three');

How can i determine the unique id with one define ? Like this:

var content = document.getElementByID('inner-main-container-%%');