hi,

you can try this,

as far i had tested it works,
plz let me know if there are any errors or anything to be clarified

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for i in `ls flat*`
do
echo $i > cls
val=`awk '{print substr($i,length($i)-2,3);}' cls`
mv $i file`expr $val + 0`
done
rm -f cls
exit 0
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