Clear Magento cart and quote items

gistfile1.php

<?php
  // Clear Magento cart and quote items
  $cart = Mage::getModel('checkout/cart');                
  $cart->truncate()->save(); // remove all active items in cart page
  $cart->init();

  $session= Mage::getSingleton('checkout/session');
  $quote = $session->getQuote();

  $cart = Mage::getModel('checkout/cart');
  $cartItems = $cart->getItems();
  foreach ($cartItems as $item)
  {
    $quote->removeItem($item->getId())->save();
  }

  Mage::getSingleton('checkout/session')->clear();
?>