16 files changed, 277 insertions, 0 deletions
diff --git a/challenge-251/luca-ferrari/blog-1.txt b/challenge-251/luca-ferrari/blog-1.txt
new file mode 100644
index 0000000000..ef5631ba42
--- /dev/null
+++ b/challenge-251/luca-ferrari/blog-1.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2024/01/08/PerlWeeklyChallenge251.html#task1
diff --git a/challenge-251/luca-ferrari/blog-2.txt b/challenge-251/luca-ferrari/blog-2.txt
new file mode 100644
index 0000000000..40f36701a6
--- /dev/null
+++ b/challenge-251/luca-ferrari/blog-2.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2024/01/08/PerlWeeklyChallenge251.html#task2
diff --git a/challenge-251/luca-ferrari/blog-3.txt b/challenge-251/luca-ferrari/blog-3.txt
new file mode 100644
index 0000000000..d8cf826c69
--- /dev/null
+++ b/challenge-251/luca-ferrari/blog-3.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2024/01/08/PerlWeeklyChallenge251.html#task1plperl
diff --git a/challenge-251/luca-ferrari/blog-4.txt b/challenge-251/luca-ferrari/blog-4.txt
new file mode 100644
index 0000000000..8bc8154b8b
--- /dev/null
+++ b/challenge-251/luca-ferrari/blog-4.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2024/01/08/PerlWeeklyChallenge251.html#task2plperl
diff --git a/challenge-251/luca-ferrari/blog-5.txt b/challenge-251/luca-ferrari/blog-5.txt
new file mode 100644
index 0000000000..e8326a85ec
--- /dev/null
+++ b/challenge-251/luca-ferrari/blog-5.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2024/01/08/PerlWeeklyChallenge251.html#task1plpgsql
diff --git a/challenge-251/luca-ferrari/blog-6.txt b/challenge-251/luca-ferrari/blog-6.txt
new file mode 100644
index 0000000000..57b87c236c
--- /dev/null
+++ b/challenge-251/luca-ferrari/blog-6.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2024/01/08/PerlWeeklyChallenge251.html#task2plpgsql
diff --git a/challenge-251/luca-ferrari/blog-7.txt b/challenge-251/luca-ferrari/blog-7.txt
new file mode 100644
index 0000000000..9437b6564e
--- /dev/null
+++ b/challenge-251/luca-ferrari/blog-7.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2024/01/08/PerlWeeklyChallenge251.html#task1python
diff --git a/challenge-251/luca-ferrari/blog-8.txt b/challenge-251/luca-ferrari/blog-8.txt
new file mode 100644
index 0000000000..f653f319b0
--- /dev/null
+++ b/challenge-251/luca-ferrari/blog-8.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2024/01/08/PerlWeeklyChallenge251.html#task2python
diff --git a/challenge-251/luca-ferrari/postgresql/ch-1.plperl b/challenge-251/luca-ferrari/postgresql/ch-1.plperl
new file mode 100644
index 0000000000..7152e60c8a
--- /dev/null
+++ b/challenge-251/luca-ferrari/postgresql/ch-1.plperl
@@ -0,0 +1,23 @@
+--
+-- Perl Weekly Challenge 251
+-- Task 1
+-- See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-251/>
+--
+
+CREATE SCHEMA IF NOT EXISTS pwc251;
+
+CREATE OR REPLACE FUNCTION
+pwc251.task1_plperl( int[] )
+RETURNS int
+AS $CODE$
+   my ( $nums ) = @_;
+   my $sum = 0;
+   
+   for  ( 0 .. $nums->@* - 2 ) {
+	next if $_ % 2 != 0;
+        $sum += $nums->@[ $_ ] . $nums->@[ $_ + 1 ];
+   }
+
+   return $sum;
+$CODE$
+LANGUAGE plperl;
diff --git a/challenge-251/luca-ferrari/postgresql/ch-1.sql b/challenge-251/luca-ferrari/postgresql/ch-1.sql
new file mode 100644
index 0000000000..83c215c5f6
--- /dev/null
+++ b/challenge-251/luca-ferrari/postgresql/ch-1.sql
@@ -0,0 +1,29 @@
+--
+-- Perl Weekly Challenge 251
+-- Task 1
+--
+-- See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-251/>
+--
+
+CREATE SCHEMA IF NOT EXISTS pwc251;
+
+CREATE OR REPLACE FUNCTION
+pwc251.task1_plpgsql( nums int[] )
+RETURNS int
+AS $CODE$
+DECLARE
+	s text;
+	v int := 0;
+BEGIN
+	FOR i IN 1 .. array_length( nums, 1 ) - 1 LOOP
+	    IF i % 2 = 0 THEN
+	       CONTINUE;
+	    END IF;
+
+	    v := v + ( nums[ i ]::text || nums[ i + 1 ]::text )::int;
+	END LOOP;
+
+	RETURN v;
+END
+$CODE$
+LANGUAGE plpgsql;
diff --git a/challenge-251/luca-ferrari/postgresql/ch-2.plperl b/challenge-251/luca-ferrari/postgresql/ch-2.plperl
new file mode 100644
index 0000000000..32d43ba6ef
--- /dev/null
+++ b/challenge-251/luca-ferrari/postgresql/ch-2.plperl
@@ -0,0 +1,63 @@
+--
+-- Perl Weekly Challenge 251
+-- Task 2
+-- See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-251/>
+--
+
+CREATE SCHEMA IF NOT EXISTS pwc251;
+
+/**
+ * example
+ testdb=> select pwc251.task2_plperl( array[ [ 3,  7,  8],
+                   [ 9, 11, 13],
+                   [15, 16, 17]] );
+ task2_plperl 
+--------------
+           15
+(1 row)
+*/
+CREATE OR REPLACE FUNCTION
+pwc251.task2_plperl( int[][] )
+RETURNS int
+AS $CODE$
+   my ( $matrix ) = @_;
+
+   my $max_col = undef;
+
+   # search the max column value
+   my @max_col_indexes;
+   for my $col ( 0 .. $matrix->@[ 0 ]->@* - 1 ) {
+       $max_col_index[ $col ] = undef;
+
+       for my $row ( 0 .. $matrix->@* - 1 ) {
+       	   $max_col_index[ $col ] = $matrix->@[ $row ]->[ $col ] if ( ! $max_col_index[ $col ] || $max_col_index[ $col ] < $matrix->@[ $row ]->[ $col ] );
+       }
+   }
+   for my $row ( 0 .. $matrix->@* - 1 ) {
+       for my $col ( 0 .. $matrix->@[ $row ]->@* - 1 ) {
+       	   $max_col = $matrix->@[ $row ]->[ $col ] if ( ! $max_col || $max_col < $matrix->@[ $row ]->[ $col ] );
+       }
+   }
+
+  for my $row ( 0 .. $matrix->@* - 1 ) {
+      my $current_min = undef;
+      my $current_min_index = 0;
+      
+     for my $col ( 0 .. $matrix->@[ $row ]->@* - 1 ) {
+     	 if ( ! $current_min || $matrix->@[ $row ]->[ $col ] < $current_min ) {
+	    $current_min = $matrix->@[ $row ]->[ $col ];
+	    $current_min_index = $col;
+	 }
+     }
+
+     if ( $current_min == $max_col_index[ $current_min_index ] ) {
+     	return $current_min;
+     }
+
+
+  }
+
+  return -1;
+
+$CODE$
+LANGUAGE plperl;
diff --git a/challenge-251/luca-ferrari/postgresql/ch-2.sql b/challenge-251/luca-ferrari/postgresql/ch-2.sql
new file mode 100644
index 0000000000..fcdf6a6f9a
--- /dev/null
+++ b/challenge-251/luca-ferrari/postgresql/ch-2.sql
@@ -0,0 +1,16 @@
+--
+-- Perl Weekly Challenge 251
+-- Task 2
+--
+-- See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-251/>
+--
+
+CREATE SCHEMA IF NOT EXISTS pwc251;
+
+CREATE OR REPLACE FUNCTION
+pwc251.task2_plpgsql( matrix int[][] )
+RETURNS int
+AS $CODE$
+   SELECT pwc251.task2_plperl( matrix );
+$CODE$
+LANGUAGE sql;
diff --git a/challenge-251/luca-ferrari/python/ch-1.py b/challenge-251/luca-ferrari/python/ch-1.py
new file mode 100644
index 0000000000..e72f979066
--- /dev/null
+++ b/challenge-251/luca-ferrari/python/ch-1.py
@@ -0,0 +1,25 @@
+#!python
+
+#
+# Perl Weekly Challenge 251
+# Task 1
+#
+# See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-251/>
+#
+
+import sys
+
+# task implementation
+def main( argv ):
+    sum = 0
+    for i in range( 0, len( argv ) - 1 ):
+        if i % 2 != 0:
+            continue
+        sum += int( argv[ i ] + argv[ i + 1 ] )
+
+    return sum
+
+
+# invoke the main without the command itself
+if __name__ == '__main__':
+    print( main( sys.argv[ 1: ] ) )
diff --git a/challenge-251/luca-ferrari/python/ch-2.py b/challenge-251/luca-ferrari/python/ch-2.py
new file mode 100644
index 0000000000..a06c706b28
--- /dev/null
+++ b/challenge-251/luca-ferrari/python/ch-2.py
@@ -0,0 +1,59 @@
+#!python
+
+#
+# Perl Weekly Challenge 251
+# Task 2
+#
+# See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-251/>
+#
+
+import sys
+
+# task implementation
+def main( argv ):
+    matrix = []
+    row = 0
+    matrix.append( [] )
+
+    for x in argv[ 0 ]:
+        if x == ' ':
+            continue
+
+        # change row
+        if x == '|':
+            row += 1
+            matrix.append( [] )
+            continue
+
+        matrix[ row ].append( int( x ) )
+
+    # make indexes of max columns
+    max_cols = []
+    for col in range( 0, len( matrix ) ):
+        current_max = None
+        for row in range( 0, len( matrix[ 0 ] ) ):
+            if not current_max or current_max < matrix[ row ][ col ] :
+                current_max = matrix[ row ][ col ]
+
+        max_cols.append( current_max )
+
+    for row in range( 0, len( matrix ) ):
+        current_min = None
+        current_min_col = None
+
+        for col in range( 0, len( matrix[ row ] ) ):
+            if not current_min or current_min > matrix[ row ][ col ]:
+                current_min = matrix[ row ][ col ]
+                current_min_col = col
+
+        if current_min == max_cols[ current_min_col ]:
+            return current_min
+
+    return -1
+
+
+
+
+# invoke the main without the command itself
+if __name__ == '__main__':
+    print( main( sys.argv[ 1: ] ) )
diff --git a/challenge-251/luca-ferrari/raku/ch-1.p6 b/challenge-251/luca-ferrari/raku/ch-1.p6
new file mode 100644
index 0000000000..c0ba780273
--- /dev/null
+++ b/challenge-251/luca-ferrari/raku/ch-1.p6
@@ -0,0 +1,17 @@
+#!raku
+
+#
+# Perl Weekly Challenge 251
+# Task 1
+#
+# See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-251/>
+#
+
+sub MAIN( *@nums where { @nums.elems == @nums.grep( * ~~ Int ).elems and @nums.elems %% 2 } ) {
+    my $sum = 0;
+    for @nums -> $l, $r {
+	$sum += $l ~ $r;
+    }
+
+    $sum.say;
+}
diff --git a/challenge-251/luca-ferrari/raku/ch-2.p6 b/challenge-251/luca-ferrari/raku/ch-2.p6
new file mode 100644
index 0000000000..cbfdd4baab
--- /dev/null
+++ b/challenge-251/luca-ferrari/raku/ch-2.p6
@@ -0,0 +1,37 @@
+#!raku
+
+#
+# Perl Weekly Challenge 251
+# Task 2
+#
+# See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-251/>
+#
+
+sub MAIN() {
+
+    my $matrix = [ [ 3,  7,  8],
+                   [ 9, 11, 13],
+                   [15, 16, 17] ];
+
+    my @max-col;
+    for 0 ..^ $matrix[ 0 ].elems -> $col {
+	my @current-col.push: $matrix[ $_ ][ $col ] for 0 ..^ $matrix.elems;
+	@max-col[ $col ] = @current-col.max;
+    }
+
+    for 0 ..^ $matrix.elems -> $row {
+	my $min = Nil;
+	my $min-col = Nil;
+
+	for 0 ..^ $matrix[ $row ].elems -> $col {
+	    if ( ! $min ||  $matrix[ $row ][ $col ] < $min ) {
+		$min-col = $col;
+		$min = $matrix[ $row ][ $col ];
+	    }
+	}
+
+	$min.say and exit if ( @max-col[ $min-col ] == $min );
+    }
+
+    '-1'.say;
+}