8 files changed, 106 insertions, 0 deletions
diff --git a/challenge-156/luca-ferrari/blog-1.txt b/challenge-156/luca-ferrari/blog-1.txt
new file mode 100644
index 0000000000..768974fdff
--- /dev/null
+++ b/challenge-156/luca-ferrari/blog-1.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2022/03/17/PerlWeeklyChallenge156.html#task1
diff --git a/challenge-156/luca-ferrari/blog-2.txt b/challenge-156/luca-ferrari/blog-2.txt
new file mode 100644
index 0000000000..ec53607e53
--- /dev/null
+++ b/challenge-156/luca-ferrari/blog-2.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2022/03/17/PerlWeeklyChallenge156.html#task2
diff --git a/challenge-156/luca-ferrari/blog-3.txt b/challenge-156/luca-ferrari/blog-3.txt
new file mode 100644
index 0000000000..660a9db396
--- /dev/null
+++ b/challenge-156/luca-ferrari/blog-3.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2022/03/18/PerlWeeklyChallenge156.html#task1plperl
diff --git a/challenge-156/luca-ferrari/blog-4.txt b/challenge-156/luca-ferrari/blog-4.txt
new file mode 100644
index 0000000000..2357b1a51b
--- /dev/null
+++ b/challenge-156/luca-ferrari/blog-4.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2022/03/18/PerlWeeklyChallenge156.html#task2plperl
diff --git a/challenge-156/luca-ferrari/postgresql/ch-1.sql b/challenge-156/luca-ferrari/postgresql/ch-1.sql
new file mode 100644
index 0000000000..70a4513be3
--- /dev/null
+++ b/challenge-156/luca-ferrari/postgresql/ch-1.sql
@@ -0,0 +1,35 @@
+CREATE SCHEMA IF NOT EXISTS pwc156;
+
+CREATE OR REPLACE FUNCTION
+pwc156.is_prime( int )
+RETURNS bool
+AS $CODE$
+   return 0 if $_[0] <= 1;
+   for my $i ( 2 .. $_[0] - 1 ) {
+       return 0 if $_[0] % $i == 0;
+   }
+
+   return 1;
+$CODE$
+LANGUAGE plperl;
+
+
+CREATE OR REPLACE FUNCTION
+pwc156.sumbits( int[] )
+RETURNS int
+AS $CODE$
+   my $sum = 0;
+   for my $bit ( @{$_[0]} ) {
+       $sum += $bit;
+   }
+
+   return $sum;
+$CODE$
+LANGUAGE plperl;
+
+
+
+SELECT n
+FROM generate_series( 1, 1000 ) n
+WHERE pwc156.is_prime( pwc156.sumbits( regexp_split_to_array( n::bit(10)::text, '' )::int[] ) )
+LIMIT 10;
diff --git a/challenge-156/luca-ferrari/postgresql/ch-2.sql b/challenge-156/luca-ferrari/postgresql/ch-2.sql
new file mode 100644
index 0000000000..ac9d22739c
--- /dev/null
+++ b/challenge-156/luca-ferrari/postgresql/ch-2.sql
@@ -0,0 +1,48 @@
+CREATE SCHEMA IF NOT EXISTS pwc156;
+
+CREATE OR REPLACE FUNCTION
+pwc156.weird( int )
+RETURNS bool
+AS $CODE$
+
+use Algorithm::Knapsack;
+my @divisors;
+
+for my $i ( 2 .. $_[0] - 1 ) {
+   push @divisors, $i if $_[0] % $i == 0;
+}
+
+my $sum = 0;
+for my $i ( @divisors ) {
+   $sum += $i;
+}
+
+
+return 0 if $sum <= $_[0];
+
+my $knapsack = Algorithm::Knapsack->new(
+    capacity => $_[0],
+    weights  => \@divisors,
+);
+ 
+$knapsack->compute();
+ 
+foreach my $solution ($knapsack->solutions()) {
+    my @founds = @divisors[ $solution->@* ];
+    my $sum = 0;
+    $sum += $_ for ( @founds );
+    return 0 if $sum == $_[0];
+ 
+}
+
+
+return 1;
+$CODE$
+LANGUAGE plperlu;
+
+
+
+
+SELECT n
+FROM generate_series( 1, 100 ) n
+WHERE pwc156.weird( n );
diff --git a/challenge-156/luca-ferrari/raku/ch-1.p6 b/challenge-156/luca-ferrari/raku/ch-1.p6
new file mode 100644
index 0000000000..3b3bcc727a
--- /dev/null
+++ b/challenge-156/luca-ferrari/raku/ch-1.p6
@@ -0,0 +1,11 @@
+#!raku
+
+sub MAIN( Int $limit where { $limit > 0 } = 10 ) {
+    my @pernicious = lazy gather {
+	for 1 .. Inf {
+	    take $_ if $_.base( 2 ).comb.sum.is-prime;
+	}
+    };
+
+    @pernicious[ 0 .. $limit - 1 ].join( ', ' ).say;
+}
diff --git a/challenge-156/luca-ferrari/raku/ch-2.p6 b/challenge-156/luca-ferrari/raku/ch-2.p6
new file mode 100644
index 0000000000..9788f65fbe
--- /dev/null
+++ b/challenge-156/luca-ferrari/raku/ch-2.p6
@@ -0,0 +1,8 @@
+#!raku
+
+sub MAIN( Int $n where { $n > 0 } ) {
+    my @divisors = ( 1 .. $n - 1 ).grep( $n %% * );
+    '0'.say and exit if @divisors.sum <= $n
+		     || @divisors.combinations.map( *.sum ).grep( * == $n ).elems > 0;
+    '1'.say;
+}