I'm not sure what you mean by 'Some keys are redundant', but here is one way to delete all hash elements except for the key whose value is the maximum: 
use strict;   
use warnings;
use List::Util qw(max);
use Data::Dumper;

my %h = (a=>2, b=>8, c=>7);
my $max = max(values %h);
for (keys %h) {
    delete $h{$_} unless $h{$_} == $max
}
print Dumper(\%h);

__END__
$VAR1 = {
          'b' => 8
        };

[download]
If this is not what you are looking for, post some of your hash contents and some of your code.

In reply to Re: Hash Question by toolic
in thread Hash Question by perl_n00b

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