It looks like you are over-thinking the algorithm. :-) 

my %hash;
for my $nar ( @nar ) {
    my ( $key1, $key2 ) = split /\s*-\s*/, shift @$nar;
    push @{ $hash{ $key1 }{ $key2 } }, $nar;
    }

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In reply to Re: Constructing HoHoA from AoA by Anonymous Monk
in thread Constructing HoHoA from AoA by neversaint

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