Re: confused with a hash which contains reversed keys

You can iterate over the hash, and build a new one:

my %uniq;
for (keys %hash){
    if (exists $uniq{scalar reverse $_}){
        $uniq{scalar reverse $_} += $hash{$_};
    } else {
        $uniq{$_} = $hash{$_};
    }
}
# untested
[download]

Note that the outcome will either contain the key 'AB' or 'BA', but you don't have control over which one occurs (it's not in the spec ;-)

Comment on Re: confused with a hash which contains reversed keys Download Code

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Re^2: confused with a hash which contains reversed keys by FunkyMonk (Bishop) on Dec 03, 2007 at 13:31 UTC
Note that the outcome will either contain the key 'AB' or 'BA', but you don't have control over which one occurs So sort the keys before adding... `my %uniq; for ( keys %hash ) { my $reordered_key = join sort split ''; $uniq{$reordered_key} += $hash{$_}; } # still untested` [download] The alphabetically first one will be used (ie AB, rather than BA even if AB doesn't occur). update: Fixed ikegami's failing test case	[reply] [d/l] [select]
Re^3: confused with a hash which contains reversed keys by ikegami (Patriarch) on Dec 03, 2007 at 13:44 UTC
Sorting like that won't produce consistent results. If EA is present in the original hash but not AE, you'll end up with EA instead of AE. Sort the chars of the key rather than the order in which they are fetched to avoid guessing under which key a particular value is located.	[reply]
Re^4: confused with a hash which contains reversed keys by Anonymous Monk on Dec 03, 2007 at 14:57 UTC
you have right with the sorting but i can't understand what do you mean "Sort the chars of the key " how i can do that by using the code of the first answer ?	[reply]
Re^3: confused with a hash which contains reversed keys by Anonymous Monk on Dec 03, 2007 at 13:39 UTC
thanks a lot for your help!It works correctly	[reply]