fiddle for Isaac 1

by Horia-Adrian Ionescu

HTML

<body>
  <div id="one">
    <p>One</p>
  </div>
  <div id="two">
    <p>Two</p>
  </div>
  <div id="three">
    <div id="dontFindMe">
      <p id="theOne">Three</p>
    </div>
  </div>
</body>

JavaScript

/* write this function such that when you pass an ID, it returns a reference to the DOM element, pretending that document.getElementByID doesn't exist */

function findById(id) {
  //return document.querySelector("#"+id);// not good on older browsers
  var elements = document.getElementsByTagName("*");
  for(var i = 0; i < elements.length; i++){
  	if(elements[i].id === id){
    	return elements[i];
    }
  }
  console.log("not found");
}

findById('theOne').style.border = '1px solid black';