Add and remove links dynamically

HTML

<button id="add">Add link</button>
<button id="remove">Remove link</button>
<ul id="list">
</ul>

JavaScript

var i = 0;
window.onload = init;

function init() {
  document.getElementById('add').onclick = add;
  document.getElementById('remove').onclick = remove;
}

function add() {
  var ul = document.getElementById('list');
  var li = document.createElement('li');
  var a = document.createElement('a');
  a.setAttribute('href', 'www.google.it');
  a.innerText = (i + 1).toString();
  li.appendChild(a);
  ul.appendChild(li);
  i++;
}

function remove() {
  if (i == 0)
    return;
  var ul = document.getElementById('list');
  ul.removeChild(ul.lastChild);
  i--;
}