#!/bin/bash
v=$1
#validation
if [ $(echo $v | grep -E -c '([[:xdigit:]]{8})-([[:xdigit:]]{4})-([[:xdigit:]]{4})-([[:xdigit:]]{4})-([[:xdigit:]]{12})') == 0 ];
then echo "Invalid UUID!"
exit
fi
echo ${v:6:2}${v:4:2}${v:2:2}${v:0:2}"-"${v:11:2}${v:9:2}"-"${v:16:2}${v:14:2}${v:18:20}