Group of XML Tags with Nesting in PHP

Now suppose we have several tags containing nested ones inside:

<root>
	<tag>
		<elem>text1</elem>
	</tag>
	<tag>
		<elem>text2</elem>
	</tag>
	<tag>
		<elem>text3</elem>
	</tag>
</root>

Let's loop through our tags and output the values of the nested tags:

<?php
	foreach ($xml->tag as $tag) {
		echo $tag->elem; // 'text1', 'text2', 'text3'
	}
?>

Given the following XML:

<root>
	<user>
		<name>john</name>
		<surn>smit</surn>
	</user>
	<user>
		<name>eric</name>
		<surn>wils</surn>
	</user>
	<user>
		<name>kyle</name>
		<surn>tayl</surn>
	</user>
</root>

Display the name and surname of each user.

Given the following XML:

<root>
	<product cost="100" amount="3">
		<name>prod1</name>
		<category>cat1</category>
	</product>
	<product cost="200" amount="4">
		<name>prod2</name>
		<category>cat2</category>
	</product>
	<product cost="300" amount="5">
		<name>prod3</name>
		<category>cat3</category>
	</product>
</root>

Display the name, category, price and quantity of each product.