#!/usr/bin/perl -w
use strict;
use autodie;

my $dna;
open FH, '<', 'fluseq.txt';
my $data = do {local $/; <FH>};

if ($data =~ /ORIGIN(.*)/s)
{
    $dna = $1;
    $dna =~ s/\s+//g;
    $dna =~ s/\d+//g;
    $dna =~ s/\/\///;
}

print $dna;

close FH;