JSFiddle - React, Tailwind, and code Playground
HTML
<input id="mhm" value="1"/>
<button>go</button>
JavaScript
$("button").click(function(){
var v = $("#mhm").val();
$("#mhm").val(add(v));
});
function add(value) {
return value.length < 3 ? add("0"+value) : value
}