JSFiddle - React, Tailwind, and code Playground

HTML

<div id="1">1</div>
<div id="2">2</div>

CSS

div {
    width: 50em;
    height: 2em;
    background-color: #eee;
    text-align: center;
    margin: 1em;
}

JavaScript

for(var i = 1; i <= 2; i++) {
    addEvent(i);
}

function addEvent(i) {
    document.getElementById(i).addEventListener('click', function() {
        alert(i);
    });
}