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

my (@seq, $x);
open (F, "< xyz") || die "Cannot open file\n";

while (<F>) { 
    chomp($_); 
    if (length($_) > 0) { 
        $seq[$x] .= $_; 
    } else { 
        $x++; 
    } 
}
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Mago
mago@rio.pm.org