XSLT - Generate unique id fora each distinct value - xslt-1.0

Question

I'm trying to generate a unique id for each distinct value using XSLT-1.0. I have a XSMLstructure and every time when I find the same value in tag I would like to generate a unique id into the output tag .
Input XML:
<EMPLOYEES>
<EMPLOYEE>
<ID>1</ID>
<NAME>AAA</NAME>
</EMPLOYEE>
<EMPLOYEE>
<ID>2</ID>
<NAME>AAA</NAME>
</EMPLOYEE>
<EMPLOYEE>
<ID>3</ID>
<NAME>BBB</NAME>
</EMPLOYEE>
</EMPLOYEES>
Desired output:
<RESULT>
<EMPLOYEE>
<ID>1</ID>
<GROUP>1</GROUP>
</EMPLOYEE>
<EMPLOYEE>
<ID>2</ID>
<GROUP>1</GROUP>
</EMPLOYEE>
<EMPLOYEE>
<ID>3</ID>
<GROUP>2</GROUP>
</EMPLOYEE>
</RESULT>

Answer 1

You could use a variation of Muenchian grouping:
XSLT 1.0
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:key name="emp-by-name" match="EMPLOYEE" use="NAME" />
<xsl:template match="/EMPLOYEES">
<RESULT>
<xsl:for-each select="EMPLOYEE">
<xsl:copy>
<xsl:copy-of select="ID"/>
<GROUP>
<xsl:value-of select="generate-id(key('emp-by-name', NAME)[1])"/>
</GROUP>
</xsl:copy>
</xsl:for-each>
</RESULT>
</xsl:template>
</xsl:stylesheet>
The format of the unique id depends on the processor you use: for example, using libxslt you might see a result like:
<?xml version="1.0" encoding="UTF-8"?>
<RESULT>
<EMPLOYEE>
<ID>1</ID>
<GROUP>idm86101615952</GROUP>
</EMPLOYEE>
<EMPLOYEE>
<ID>2</ID>
<GROUP>idm86101615952</GROUP>
</EMPLOYEE>
<EMPLOYEE>
<ID>3</ID>
<GROUP>idm86101613584</GROUP>
</EMPLOYEE>
</RESULT>
while MSXML can produce:
<?xml version="1.0"?>
<RESULT>
<EMPLOYEE>
<ID>1</ID>
<GROUP>IDOECYH2JCFIENET332KVV31ACSEILRTQLIHKWOCNC1WN5QJBD3AH</GROUP>
</EMPLOYEE>
<EMPLOYEE>
<ID>2</ID>
<GROUP>IDOECYH2JCFIENET332KVV31ACSEILRTQLIHKWOCNC1WN5QJBD3AH</GROUP>
</EMPLOYEE>
<EMPLOYEE>
<ID>3</ID>
<GROUP>IDZZBORVA3LQGFPDQLO51JC1X1JDCTYLF430BB43GE1YQ1D54SHZSB</GROUP>
</EMPLOYEE>
</RESULT>