Find duplicates

perl.pl

sub findDuplicates {
    # @info is an array of hashrefs
    my @keys = keys $info[0];
    grep { 
        for (my $i = 0; $i < scalar(@info) - 1; $i++) {
            # I want to remove any keys from @keys if two adjacent
            # values in $info are unequal for the same key
            $info[$i]{$_} eq $info[$i]{$_} 
        }
    } @keys;
    return @keys;
}