Get Configurable Product SKU and Its Simple Product SKU in Cart Page Magento

Put this code at templet/checkout/cart/item/default.phtml after this line "$_item = $this->getItem();"

<?php
echo $temp = $_item->getProductId();
echo "<br/>";
$_product = Mage::getModel('catalog/product')->load($temp);
echo "Config. Product :";
echo $_product->getSku();
echo "<br/>";

echo "Simple Product :";
echo $_item->getSku();
?>

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