Searching for elements in XML

Hi
 
In terms of performance which is better if I'm searching for a number of
elements in the XML file and I don't care about the order:
 
Let's say I'm searching for elements a, b and c:
 
<xsl:for-each select="//a|//b|//c">
</xsl:for-each>
 
or
 
<xsl:for-each select="//a">
</xsl:for-each>
 
<xsl:for-each select="//b">
</xsl:for-each>
  
<xsl:for-each select="//c">
</xsl:for-each>
 
or is there a better way?
 
Thanks in advance
 
Regards,
 
Néstor Boscán