Change input value onclick button - pure javascript or jQuery

Question

I have two buttons and if I click on some button I need to change value in input text and change total price (product price * value of button - 2 or 4 Qty).

I know

Answer 1

using html5 data attribute...

try this

Html

Product price: $500


Total price: $500





Total

JS

$(function(){
$('input:button').click(function () {
  $('#count').val($(this).data('quantity') * $('#product_price').text());
});
});

fiddle here