#!/usr/bin/perl

use strict;
use Data::Dumper;

open (IN, "in.txt");

my @element;
my $data;
while (<IN>) {

    chomp ($_);

    if ($_ =~ /^>/) {
        if ($data) {
            push @element, $data;
            $data = '';
        }
        push @element, $_;
    } else {
        $data .= $_ . "\n"
    }
}
push @element, $data;

print Dumper \@element;