JSFiddle - React, Tailwind, and code Playground

HTML

<button id='switch'>Inverter</button>

<input id='in' value='100' type='text'/>
<input id='out' value='001' type='text'/>

JavaScript

var $button = document.getElementById('switch'),
    $out    = document.getElementById('out'),
    $in     = document.getElementById('in');

$button.addEventListener('click', function(){
	var temp = $out.value;
    $out.value = $in.value;
    $in.value = temp;
}, false);