A Hash of Hashes simply looks something like: 
$ perl -MData::Dumper -e"%h=(a=>{1..4},b=>{5..8});print Dumper\%h"
$VAR1 = {
          'a' => {
                   '1' => 2,
                   '3' => 4
                 },
          'b' => {
                   '7' => 8,
                   '5' => 6
                 }
        };

[download]
What you probably want instead is a Hash of Lists. Try this: 
use strict;
use warnings;
use Data::Dumper;

...

my %hash;
while (<INPUT>) {
   chomp;
   my @line = split /\s+/, $_;
   my ($key1,$key2) = (shift @line, shift @line);
   $hash{$key1} = $hash{$key2} = [@line];
}

print Dumper \%hash;

[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: Hash of Hash by jeffa
in thread Hash of Hash by Anonymous Monk

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