JSFiddle - React, Tailwind, and code Playground

HTML

<div id="v1"></div>
<div id="v2"></div>

JavaScript

function a() {
	var myval = 0;
  return function(x) { myval += x; return myval; };
}
var f = a();
document.getElementById('v1').innerHTML = f(5);
document.getElementById('v2').innerHTML = f(7);