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in reply to How to remove duplicate key/value pairs in hash of array

You can eliminate duplicate values by inverting the hash (turning key/value pairs into value/key pairs) and then re-inverting. 
%hash = (a => 1, b => 1, c => 2);

%hash = reverse %hash; # key/value -> value/key
%hash = reverse %hash;

foreach $key ( keys %hash ) {
    print $key, " => ", $hash{$key}, "\n";
}

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Re^2: How to remove duplicate key/value pairs in hash of array
by bdalzell (Sexton) on Feb 04, 2009 at 15:18 UTC
    this works to remove duplicate values but if the keys are numeric it removes the lower numbered key value pairs. how would you remove the higher key numbered key value pairs retaining the key/value pair with the lowest value key?
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