Re: small grouping task

desired output. Only the <input>.....<br/> pairs are altered
--------------------------------------------------------------------
<r>
   <p>text</p>
   <randomtag>surronding xhtml</randomtag>
<p class="problem">some <b>xhtml</b> with<br/> no inputs<br/>
 <ul class="m">
  <li class="m"> <span class="p">a</span><b>d </b></li>
  <li class="m"> <b>g </b><span class="p">b</span></li>
 </ul>
   <p>more</p> generic <b>xhtml</b> with<br/> no inputs<img src="l"/>
</p>
<b>a</b>surronding xhtml<b>b</b>
</r>
------------------------------------------------------------------------------

current incorrect output,
note: has  missing items and misplaced items.
---------------------------------------------

<?xml version="1.0" encoding="UTF-8"?>
<r>
   <p>text</p>
   <randomtag>surronding xhtml</randomtag>
  <ul class="m">
     <li class="m">
        <span class="p">a</span>
        <b>d </b>
     </li>
     <li class="m">
        <b>g </b>
        <span class="p">b</span>
        <p>more</p> generic <b>xhtml</b> with no inputs<img src="l"/>
     </li>
  </ul>
  <b>a</b>surronding xhtml<b>b</b>
</r>

current stylesheet (same as Ken's)
----------------------------------
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
               version="2.0">

<xsl:template match="p[@class = 'problem' and input]">
 <!--start the list-->
 <ul class="m">
   <!--find the members of the list, assuming multiple items per member-->
   <xsl:for-each-group select="node()" group-starting-with="input">
     <xsl:if test="self::input"><!--found a group with an input-->
       <li class="m">
         <!--copy everything except <br/> elements-->
         <xsl:apply-templates select="current-group()[position()>1]
                                                     [not(self::br)]"/>
       </li>
     </xsl:if>
   </xsl:for-each-group>
 </ul>
</xsl:template>

<xsl:template match="@*|node()"><!--identity for all other nodes-->
 <xsl:copy>
   <xsl:apply-templates select="@*|node()"/>
 </xsl:copy>
</xsl:template>