Task 2 plperl done

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diff --git a/challenge-219/luca-ferrari/postgresql/ch-2.plperl b/challenge-219/luca-ferrari/postgresql/ch-2.plperl
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+--
+-- Perl Weekly Challenge 219
+-- Task 2
+-- See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-219/>
+--
+
+CREATE SCHEMA IF NOT EXISTS pwc219;
+
+CREATE OR REPLACE FUNCTION
+pwc219.task2_plperl( int[], int[] )
+RETURNS int
+AS $CODE$
+   my ( $c, $days ) = @_;
+   my $costs = {};
+   $costs->{ 1 }  = $c->@[ 0 ];
+   $costs->{ 7 }  = $c->@[ 1 ];
+   $costs->{ 30 } = $c->@[ 2 ];
+
+   my @evaluated;
+   my $current_cost = ( scalar $days->@* ) * $costs->{ 1 };
+   push @evaluated, { cost => 0, days => $days };
+
+   while ( ( scalar @evaluated ) > 0 ) {
+   	 my $entry = shift @evaluated;
+
+	 if ( $entry->{ days }->@* == 0 ) {
+	    $current_cost = $entry->{ cost } if ( $entry->{ cost } < $current_cost );
+	 }
+	 else {
+	      next if ( $entry->{ cost } >= $current_cost );
+
+	      my $begin_date = $entry->{ days }->[ 0 ];
+	      for my $duration ( keys $costs->%* ) {
+	      	  my $end_date = $begin_date + $duration - 1;
+		  my $cost = $entry->{ cost } + $costs->{ $duration };
+		  my @remaining_days =  grep { $_ > $end_date }  $entry->{ days }->@*;
+		  push @evaluated, { cost => $cost, days => \@remaining_days };
+	      }	  
+	 }
+   }
+
+   return $current_cost;
+
+$CODE$
+LANGUAGE plperl;