JSFiddle - React, Tailwind, and code Playground
by RoryMcCrossan
HTML
<div id="2" class="maindiv">test</div>
<div id="5" class="maindiv">test</div>
<div id="3" class="maindiv">test</div>
<div id="1" class="maindiv">test</div>
<div class="maindiv">test</div>
<div id="4" class="maindiv">test</div>
JavaScript
var ids = $("div[id]").map(function() {
return this.id;
}).get();
var highest = Math.max.apply( Math, ids );
var lowest = Math.min.apply( Math, ids );
alert(highest)
alert(lowest)