can anyone write a perl code for that???

Lots of people here can do that. Hopefully you can do in the near future! Read the perl docs to find out what the following does: 

perl -n0777 -e 'print s/>/>/g,"\n"' fastafile

[download]
perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re: Counting no of '>' symbol in a file by shmem
in thread Counting no of '>' symbol in a file by GSperlbio

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