JSFiddle - React, Tailwind, and code Playground

by antyrat

HTML

<div class="box1"></div>
<div class="box9"></div>
<div class="box4"></div>

JavaScript

var biggestNum = 0;
$('div[class^="box"]').each(function(){
    var currentNum = parseInt($(this).attr('class').replace('box', ''), 10);
    if(currentNum > biggestNum) {
        biggestNum = currentNum;
    }
});

alert(biggestNum);