JSFiddle - React, Tailwind, and code Playground

by luka kupunia

HTML

<input type="text"class="demo">
<input type="text"class="demo">
<input type="text"class="demo">



<input type="text" id="result">


<input type="submit" id="submit">

CSS

input#result {
  display: block;
}

JavaScript

var a = document.querySelectorAll('.demo');
var b = document.querySelector('#result');

for( var i = 0; i < a.length; i++ ){
	a[i].addEventListener('keyup',function(){
  		if(this.value.length > 1){
      	a[2].focus();
      }
  		b.value = a[0].value + a[1].value + 		a[2].value;
  })
}