How to read multiple child elements and write into different xml format

[umesh_epub]

My input is like This

<articleorder>
<group>
<article-ref rid="1"/>
</group>
<group>
<group>
<title><![CDATAGroupI]></title>
<article-ref rid="2"/>
</group>
</group>
<group>
<group>
<title><![CDATAGroupI]></title>
<title><![CDATAGroupII]></title>
<article-ref rid="4"/>
</group>
</group>
<group>
<group>
<title><![CDATAGroupI]></title>
<title><![CDATAGroupII]></title>
<article-ref rid="8"/>
</group>
</group>
<group>
<group>
<title><![CDATAGroupI]></title>
<title><![CDATAGroupII]></title>
<title><![CDATAGroupIII]></title>
<article-ref rid="5"/>
</group>
</group>
<group>
<article-ref rid="6"/>
</group></articleorder>

Output i want like this

<group>
<article-ref rid="1"/>
<group>
<title>GroupI</title>
<article-ref rid="2"/>
<group>
<title>GroupII</title>
<article-ref rid="4"/>
<article-ref rid="8"/>
<group>
<title>GroupIII</title>
<article-ref rid="5"/>
</group>
</group>
</group>
<article-ref rid="6"/>
</group>

[ww]

1. What have you tried? Show us your code; error messages, if any; and how your code falls short of your desires.
2. Read On asking for help
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3. While conciseness is admirable, stating your question ONLY is the title is (at least for me) disconcerting.