JSFiddle - React, Tailwind, and code Playground

by Kamlesh Kushwaha

HTML

<div class="someDiv"></div>
<div class="someDiv"></div>
<div class="someDiv"></div>
<div class="someDiv"></div>
<div class="someDiv"></div>
<div class="someDiv"></div>
<div class="someDiv"></div>
<div class="someDiv"></div>
<div class="someDiv"></div>
<div class="someDiv"></div>
<button>Click to pick X elements at random:</button>

CSS

.red {
    background: red;
}
div {
    padding:10px;
    width:30px;
    height:30px;
    border:1px solid black;
}

JavaScript

function shuffle(array) {
    var m = array.length,
        t, i;
    while (m) {
        i = Math.floor(Math.random() * m--);
        t = array[m];
        array[m] = array[i];
        array[i] = t;
    }
    return array;
}

$(function () {
    $("button").click(function () {
        var $all = $(".someDiv").removeClass("red");
        $(shuffle($all).slice(0, 3)).addClass("red");
    });
});