- Tidied up contributions by Luca Ferrari.

8 files changed, 107 insertions, 37 deletions

diff --git a/challenge-133/luca-ferrari/blog-1.txt b/challenge-133/luca-ferrari/blog-1.txt
index bc163279b2..6dc13d6def 100644
--- a/challenge-133/luca-ferrari/blog-1.txt
+++ b/challenge-133/luca-ferrari/blog-1.txt
@@ -1 +1 @@
-https://fluca1978.github.io/2021/10/11/PerlWeeklyChallegne133.html#task1
+https://fluca1978.github.io/2021/10/09/PerlWeeklyChallegne133.html#task1
diff --git a/challenge-133/luca-ferrari/blog-2.txt b/challenge-133/luca-ferrari/blog-2.txt
index 65f4a25e54..a3a9243bdf 100644
--- a/challenge-133/luca-ferrari/blog-2.txt
+++ b/challenge-133/luca-ferrari/blog-2.txt
@@ -1 +1 @@
-https://fluca1978.github.io/2021/10/11/PerlWeeklyChallegne133.html#task2
+https://fluca1978.github.io/2021/10/09/PerlWeeklyChallegne133.html#task2
diff --git a/challenge-133/luca-ferrari/raku/ch-1.p6 b/challenge-133/luca-ferrari/raku/ch-1.p6
index ef7c25b62c..0f7a2ce5c4 100644
--- a/challenge-133/luca-ferrari/raku/ch-1.p6
+++ b/challenge-133/luca-ferrari/raku/ch-1.p6
@@ -1,20 +1,18 @@
 #!raku
 
 
-sub MAIN( Int $limit where { $limit > 0 } = 5 ) {
-    my @digits = 1 .. 9;
-    @digits.push: 0;
-    my $start =  @digits.join;
-    
-    my @pandigital = lazy gather {
-        for $start ..^ Inf -> $current {
-            next if $start ~~ / ^0+ /;
-            my $found = 0;
-            $found += $current.comb.grep( $_ ).so ?? 1 !! 0 for @digits;
-            take $current if $found >= @digits.elems;
-        }
+sub MAIN( Int $n where { $n > 0 } ) {
+    $n.say and exit if $n == 1;
+
+    my Int $current-solution = $n +> 1;  # divide by two
+    my Int $next-solution    = 0;
+    while ( $next-solution < $current-solution ) {
+        $next-solution    = ( $current-solution + $n / $current-solution ) +> 1 if ! $next-solution;
+        ( $current-solution, $next-solution ) = $next-solution,
+                                                ( $next-solution + $n / $next-solution ) +> 1;
+        
     }
 
-    @pandigital[ $_ ].say for 0 ..^ $limit;
+    $current-solution.say;
 
 }
diff --git a/challenge-133/luca-ferrari/raku/ch-2.p6 b/challenge-133/luca-ferrari/raku/ch-2.p6
index 5538af30b1..d2aaf350f4 100644
--- a/challenge-133/luca-ferrari/raku/ch-2.p6
+++ b/challenge-133/luca-ferrari/raku/ch-2.p6
@@ -1,34 +1,50 @@
 #!raku
 
+# a lazy list of all prime numbers
+my @PRIMES = grep {.is-prime}, 1..*;
 
-sub MAIN( Int $cols where { $cols > 0 } = 5, Int $rows where { $rows > 0 } = 3 ) {
-    my @table;
-    my @distinct;
+# divide a number into a list of its own factors
+multi do-factor( 1 ) { (1) }
+multi do-factor( Int $n where { $n > 1 } ) {
+    my $needle =  $n;
+    my @factors;
 
-    # table header
-    "  x\t|\t".print;
-    ( 1 .. $cols ).join( "\t" ).say;
-    "--------|--------".print;
-    ( "-" x 8 x $cols ).say;
+    for @PRIMES -> $current-factor {
+        # stop if we got a bigger number
+        last if $current-factor > $needle;
 
+        # skip if the number is not a divisor of what we are searching for
+        next unless $needle %% $current-factor;
 
+        # if here, it is a good factor
+        @factors.push: $current-factor;
 
-    
-    for 1 .. $rows -> $current-row {
-        for 1 .. $cols -> $current-col {
-            my $value = $current-row * $current-col;
-            @table[ $current-row - 1 ].push: $value;
-            @distinct.push: $value if ! @distinct.grep( $value );
-        }
+        # compute the remainder
+        $needle /= $current-factor;
     }
 
-    # print the table
-    for 1 .. $rows {
-        "  $_\t|\t".print;
-        @table[ $_ - 1 ].join( "\t" ).say;
-    }
+    
+    @factors.sort;
+    
+
+}
 
-    "\nDistinct values: ".say;
-    @distinct.join( ', ' ).say;
 
+# It is a smith number if the sum of the digits
+# is the sum of the factors
+sub is-smith-number( Int $n where { $n > 0 } ) {
+    return $n.comb.sum == do-factor( $n ).sum;
+}
+
+
+sub MAIN( Int $limit where { $limit > 0 } = 10 ) {
+
+    my @smith-numbers;
+    for 1 .. Inf {
+        next if ! is-smith-number( $_ );
+        @smith-numbers.push: $_;
+        last if @smith-numbers.elems == $limit;
+    }
+
+    @smith-numbers.join( "\n" ).say;
 }
diff --git a/challenge-134/luca-ferrari/blog-1.txt b/challenge-134/luca-ferrari/blog-1.txt
new file mode 100644
index 0000000000..bc163279b2
--- /dev/null
+++ b/challenge-134/luca-ferrari/blog-1.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2021/10/11/PerlWeeklyChallegne133.html#task1
diff --git a/challenge-134/luca-ferrari/blog-2.txt b/challenge-134/luca-ferrari/blog-2.txt
new file mode 100644
index 0000000000..65f4a25e54
--- /dev/null
+++ b/challenge-134/luca-ferrari/blog-2.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2021/10/11/PerlWeeklyChallegne133.html#task2
diff --git a/challenge-134/luca-ferrari/raku/ch-1.p6 b/challenge-134/luca-ferrari/raku/ch-1.p6
new file mode 100644
index 0000000000..ef7c25b62c
--- /dev/null
+++ b/challenge-134/luca-ferrari/raku/ch-1.p6
@@ -0,0 +1,20 @@
+#!raku
+
+
+sub MAIN( Int $limit where { $limit > 0 } = 5 ) {
+    my @digits = 1 .. 9;
+    @digits.push: 0;
+    my $start =  @digits.join;
+    
+    my @pandigital = lazy gather {
+        for $start ..^ Inf -> $current {
+            next if $start ~~ / ^0+ /;
+            my $found = 0;
+            $found += $current.comb.grep( $_ ).so ?? 1 !! 0 for @digits;
+            take $current if $found >= @digits.elems;
+        }
+    }
+
+    @pandigital[ $_ ].say for 0 ..^ $limit;
+
+}
diff --git a/challenge-134/luca-ferrari/raku/ch-2.p6 b/challenge-134/luca-ferrari/raku/ch-2.p6
new file mode 100644
index 0000000000..5538af30b1
--- /dev/null
+++ b/challenge-134/luca-ferrari/raku/ch-2.p6
@@ -0,0 +1,34 @@
+#!raku
+
+
+sub MAIN( Int $cols where { $cols > 0 } = 5, Int $rows where { $rows > 0 } = 3 ) {
+    my @table;
+    my @distinct;
+
+    # table header
+    "  x\t|\t".print;
+    ( 1 .. $cols ).join( "\t" ).say;
+    "--------|--------".print;
+    ( "-" x 8 x $cols ).say;
+
+
+
+    
+    for 1 .. $rows -> $current-row {
+        for 1 .. $cols -> $current-col {
+            my $value = $current-row * $current-col;
+            @table[ $current-row - 1 ].push: $value;
+            @distinct.push: $value if ! @distinct.grep( $value );
+        }
+    }
+
+    # print the table
+    for 1 .. $rows {
+        "  $_\t|\t".print;
+        @table[ $_ - 1 ].join( "\t" ).say;
+    }
+
+    "\nDistinct values: ".say;
+    @distinct.join( ', ' ).say;
+
+}