Parse OIDs?

[gqwill69]

I am unable to get the exact interface number from an snmpwalk, but I am able to get an interface description which has the same number in it. I am just not sure how to parse out the number only...

snmpwalk -v1 -cXXXX y.y.y.y .1.3.6.1.4.1.562.36.2.1.114.1.1.2
SNMPv2-SMI::enterprises.562.36.2.1.114.1.1.2.200 = STRING: "AtmIf/200"
SNMPv2-SMI::enterprises.562.36.2.1.114.1.1.2.201 = STRING: "AtmIf/201"
SNMPv2-SMI::enterprises.562.36.2.1.114.1.1.2.202 = STRING: "AtmIf/202"

<oid_index>.1.3.6.1.4.1.562.36.2.1.114.1.1.2</oid_index>
<oid_index_parse>OID/REGEXP:.*\.([0-9]{1,4}\.[0-9]{1,4}\.[0-9]{1,4})$</oid_index_parse>

I have tried to find answers by searching, but to no avail.
Would anyone be able to help?

Thanks