two xml match/diffes

[Charlie]

Hi all,

I'm new to the xquery and want to have a query to join
two xml files to find the matches and differences, e.g
a.xml:
<root1>
<a1>1</a1>
<a2>3</a2>
<a3>5</a3>
</root1>

b.xml:
<root2>
<b1>1</b1>
<b2>2</b2>
<b3>3</b3>
</root2>

and I'd like to have a result similar to this:
<result>
<same><s1>1</s1><s2>3</s2></same>
<root1><a3>5<a3></root1>
<root2><b2>2</b2></root2>
</result>

How can I do this kind of query?
TIA,
C


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