i think you meant this: 
my %revhash;

push @{$revhash{$hash{$_}}}, $_ for keys %hash;

for (sort keys %revhash)
{
    print "$_ => @{$revhash{$_}}\n";
}

[download]

In reply to RE: Inverting a hash to get all keys for this value by mdillon
in thread Inverting a hash to get all keys for this value by merlyn

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