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+-- Perl Weekly Challenge 195
+-- Task 2
+
+CREATE SCHEMA IF NOT EXISTS pwc195;
+
+CREATE OR REPLACE FUNCTION
+pwc195.task2_plperl( int[] )
+RETURNS int
+AS $CODE$
+   my ( $array ) = @_;
+   # extract only evens
+   my @evens = grep { $_ % 2 == 0 } $array->@*;
+   # classify frequency
+   my $bag = {};
+   $bag->{ $_ }++ for ( @evens );
+
+
+   # sort by frequency and value
+   my @sorted_bag =
+     map { $_->[1] }
+     sort { $a->[0] <=> $b->[0] || $a->[1] <=> $b->[1] }
+     map { [ $bag->{ $_ }, $_ ] } keys $bag->%*;
+
+
+    # the first value in the list is the
+    # one with the max frequency and the lowest value
+    return $sorted_bag[ 0 ];	  
+$CODE$
+LANGUAGE plperl;