Monks, Ive been writing a script for working with DNA (bioinformatics again!) but ive had trouble trying to put the header and the sequence into a hash. both $n and $m are defined correctly but only the $key will come out defined (even if I swap $m and $n over). Im sure its something simple but I cant work it out.

Example input: 

@lines:
>seq1
ASDFGHASDFGHJ
ERTYUIOOIUYLK
NBGFEWERTY
>seq2
BGTNHYMJUKOPK
MNBFSDFGHJ
....

[download]
my $line;
my ($m, $n);
my %all_hash = ();
foreach $line (@lines){
        chomp $line;
        if($line =~ /^>/){
                $n = "\n$line\n";
        }else{
                $m = $line;
        }
        $all_hash{ $n } = $m;
}       
print %all_hash;

[download]
any thoughts would be appreciated!

In reply to inputting into hash error by mabeuf

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.