JSFiddle - React, Tailwind, and code Playground

by Horia-Adrian Ionescu

HTML

<div id="foodiv"></div>
<hr/>
<hr/>
<div id="repdiv"></div>
<hr/>
<hr/>
<div id="timediv"></div>
<hr/>
<hr/>
<div id="prevtimediff"></div>

JavaScript

var i=0; 
var startingTime=new Date().getTime();
var previousTime = startingTime;
setInterval(foo,100);
function foo() {
    i+=1;
    var currTime = new Date().getTime();
    if (document.getElementById("foodiv").innerHTML==i) {
        //we detected a doubled value (parallel execution)
        document.getElementById("repdiv").innerHTML += "[repetition on "+i+"]";
    }
    document.getElementById("foodiv").innerHTML = i;
    document.getElementById("timediv").innerHTML = Math.floor((new Date().getTime()-startingTime)/1000);
    document.getElementById("prevtimediff").innerHTML = currTime - previousTime;
    previousTime = currTime;
}