java - How to write the x-path if the class names are available at run time(dynamically) -

<div id="gameschooser">             <div id="topmenu">                <div id="blockview">                 <div class="roombutton room1 wide">                 <div class="roombutton room2 wide">                 <div class="roombutton room3 wide">               </div>               </div>               </div> 

i have used xpath like:

 //div[@id='gameschooser']//div[contains(@class,'roombutton room1')] 

but class class="roombutton room wide dynamic, never know if class=roombutton room3 wide available , code fails

i suggest use nth-child() of css

for third child be

#blockview>div:nth-child(3)