Increase input box numbers by clicking plus sign

Increase input box numbers by clicking plus sign::

<script>

$(document).ready(function() {

$(".input a").click(function() {

var inputEl = $(this).parent().parent().children().next().children();

var qty = inputEl.val();

if ($(this).parent().hasClass("plus"))

qty++;

else

qty--;

if (qty < 0)

qty = 0;

inputEl.val(qty);

})

});

</script>

<div class="input-qty-box">

<div class="input">

<ul class="range">

<li class="item minus"><a style=" cursor:pointer">-</a></li>

<li>

<input type="text" maxlength="3" size="2" value="1" class="input-text qty text" id="quantity_wanted" name="qty">

</li>

<li class="item plus"><a style=" cursor:pointer">+</a></li>

</ul>

</div>

</div>