From 41994ccfdc6245a1586bd3b00a6c053c15707e8f Mon Sep 17 00:00:00 2001
From: Luca Ferrari <fluca1978@gmail.com>
Date: Mon, 29 Jun 2020 10:04:00 +0200
Subject: Task 1 done.

---
 challenge-067/luca-ferrari/raku/ch-1.p6 | 50 +++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 challenge-067/luca-ferrari/raku/ch-1.p6

diff --git a/challenge-067/luca-ferrari/raku/ch-1.p6 b/challenge-067/luca-ferrari/raku/ch-1.p6
new file mode 100644
index 0000000000..ae742e4567
--- /dev/null
+++ b/challenge-067/luca-ferrari/raku/ch-1.p6
@@ -0,0 +1,50 @@
+#!raku
+
+# Task 1
+# You are given two integers $m and $n. Write a script print all possible combinations of $n numbers from the list 1 2 3 … $m.
+#
+# Every combination should be sorted i.e. [2,3] is valid combination but [3,2] is not.
+
+
+sub MAIN( Int :$m where { $m > 2 }  = 5,
+          Int :$n where { $n < $m } = 2 ) {
+
+    # available digits
+    my @digits = 1 .. $m;
+    # found combinations
+    my @combinations;
+
+    for @digits -> $start {
+
+        # build the array of combinations starting with the
+        # current digits, place another one that is increased by one
+        # so to keep sorting...
+        my @combination = $start;
+        @combination.push: $start + 1;
+
+
+        # ... and all an element until I've made the array
+        while ( @combination.elems < $n ) {
+            @combination.push( @combination[ *-1 ] + 1 );
+        }
+
+
+        # the last element of the array must be the value
+        # I've got as parameter, otherwise iterate
+        while ( @combination[ *-1 ] < $m ) {
+            # clone the array because I'm going to change it!
+            @combinations.push: Array.new( @combination );
+
+
+            # increase by one every element, so it will be kept in
+            # order
+            for 1 ..^ @combination.elems {
+                @combination[ $_ ] += 1;
+            }
+        }
+
+        @combinations.push: @combination if ( @combination[ *-1 ] == $m );
+    }
+
+    @combinations.join( ", " ).say;
+}
-- 
cgit 


From 9eff05a97c7ac13a99e24ecec74b8ca84a91ed19 Mon Sep 17 00:00:00 2001
From: Luca Ferrari <fluca1978@gmail.com>
Date: Mon, 29 Jun 2020 10:16:27 +0200
Subject: Task 2 done.

---
 challenge-067/luca-ferrari/raku/ch-2.p6 | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 challenge-067/luca-ferrari/raku/ch-2.p6

diff --git a/challenge-067/luca-ferrari/raku/ch-2.p6 b/challenge-067/luca-ferrari/raku/ch-2.p6
new file mode 100644
index 0000000000..e414b630db
--- /dev/null
+++ b/challenge-067/luca-ferrari/raku/ch-2.p6
@@ -0,0 +1,25 @@
+#!raku
+
+# Task 2
+# You are given a digit string $S. Write a script to print all possible letter combinations that the given digit string could represent.
+
+
+sub MAIN( Str $S ) {
+    my %letters =
+    1 => [ '_', ',', '@' ]
+    , 2 => [ 'A', 'B', 'C' ]
+    , 3 => [ 'D', 'E', 'F' ]
+    , 4 => [ 'G', 'H', 'I' ]
+    , 5 => [ 'J', 'K', 'L' ]
+    , 6 => [ 'M', 'N', 'O' ]
+    , 7 => [ 'P', 'Q', 'R', 'S' ]
+    , 8 => [ 'T', 'U', 'V' ]
+    , 9 => [ 'W', 'X', 'Y', 'Z' ];
+
+    my @combinations;
+    for $S.comb  -> $current {
+        @combinations.push( %letters{ $current } ) if %letters{ $current }:exists;
+    }
+
+    ( [X] @combinations ).join( "\n" ).lc.say;
+}
-- 
cgit 


From 0ccc8cf05e749451a61254b0ca240fc80b3c7a12 Mon Sep 17 00:00:00 2001
From: Luca Ferrari <fluca1978@gmail.com>
Date: Mon, 29 Jun 2020 11:36:51 +0200
Subject: Blog references.

---
 challenge-067/luca-ferrari/blog-1.txt | 1 +
 challenge-067/luca-ferrari/blog-2.txt | 1 +
 2 files changed, 2 insertions(+)
 create mode 100644 challenge-067/luca-ferrari/blog-1.txt
 create mode 100644 challenge-067/luca-ferrari/blog-2.txt

diff --git a/challenge-067/luca-ferrari/blog-1.txt b/challenge-067/luca-ferrari/blog-1.txt
new file mode 100644
index 0000000000..53886516ee
--- /dev/null
+++ b/challenge-067/luca-ferrari/blog-1.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2020/06/29/PerlWeeklyChallenge67.html#task1
diff --git a/challenge-067/luca-ferrari/blog-2.txt b/challenge-067/luca-ferrari/blog-2.txt
new file mode 100644
index 0000000000..f4a8e9f455
--- /dev/null
+++ b/challenge-067/luca-ferrari/blog-2.txt
@@ -0,0 +1 @@
+https://fluca1978.github.io/2020/06/29/PerlWeeklyChallenge67.html#task2
-- 
cgit 


From e278df37b0c49be8f048866a815aa43a13e0760a Mon Sep 17 00:00:00 2001
From: Luca Ferrari <fluca1978@gmail.com>
Date: Mon, 29 Jun 2020 13:35:05 +0200
Subject: A little better implementation of task 1.

---
 challenge-067/luca-ferrari/raku/ch-1.p6 | 46 ++++++++++++++-------------------
 1 file changed, 19 insertions(+), 27 deletions(-)

diff --git a/challenge-067/luca-ferrari/raku/ch-1.p6 b/challenge-067/luca-ferrari/raku/ch-1.p6
index ae742e4567..f9d123fe1d 100644
--- a/challenge-067/luca-ferrari/raku/ch-1.p6
+++ b/challenge-067/luca-ferrari/raku/ch-1.p6
@@ -9,42 +9,34 @@
 sub MAIN( Int :$m where { $m > 2 }  = 5,
           Int :$n where { $n < $m } = 2 ) {
 
-    # available digits
-    my @digits = 1 .. $m;
     # found combinations
     my @combinations;
 
-    for @digits -> $start {
+    for 0 ..^ $m {
 
-        # build the array of combinations starting with the
-        # current digits, place another one that is increased by one
-        # so to keep sorting...
-        my @combination = $start;
-        @combination.push: $start + 1;
+        # cannot get negative numbers!
+        next if $m - $_ < $n;
 
+        # current combination
+        my @combination;
+        # push the last digit of this combination, for example m=5, n=3 -> 5
+        @combination.push: $m - $_;
 
-        # ... and all an element until I've made the array
-        while ( @combination.elems < $n ) {
-            @combination.push( @combination[ *-1 ] + 1 );
-        }
-
-
-        # the last element of the array must be the value
-        # I've got as parameter, otherwise iterate
-        while ( @combination[ *-1 ] < $m ) {
-            # clone the array because I'm going to change it!
-            @combinations.push: Array.new( @combination );
+        # fill up the combination with decreasing order
+        @combination.push( @combination[ *-1 ] - 1 )  while ( @combination.elems < $n );
+        # push this initial combination, e.g., 5,4,3
+        @combinations.push: Array.new( @combination.reverse );
 
 
-            # increase by one every element, so it will be kept in
-            # order
-            for 1 ..^ @combination.elems {
-                @combination[ $_ ] += 1;
-            }
+        # now go backwards all the digits until we reach '1' with the last digit
+        # e.g. 5,4,2; 5,4,1
+        while ( @combination[ *-1 ] > 1 ) {
+            @combination[ *-1 ] -= 1;
+            @combinations.push: Array.new( @combination.reverse );
         }
-
-        @combinations.push: @combination if ( @combination[ *-1 ] == $m );
     }
 
-    @combinations.join( ", " ).say;
+
+
+    @combinations.sort.join( ", " ).say;
 }
-- 
cgit 


From 14e647fc20118e2813d7e3aa3b31af54677b6aa5 Mon Sep 17 00:00:00 2001
From: Luca Ferrari <fluca1978@gmail.com>
Date: Mon, 29 Jun 2020 13:43:40 +0200
Subject: Brute force at task 1.

---
 challenge-067/luca-ferrari/raku/ch-1.p6 | 28 ++++++----------------------
 1 file changed, 6 insertions(+), 22 deletions(-)

diff --git a/challenge-067/luca-ferrari/raku/ch-1.p6 b/challenge-067/luca-ferrari/raku/ch-1.p6
index f9d123fe1d..a408701f34 100644
--- a/challenge-067/luca-ferrari/raku/ch-1.p6
+++ b/challenge-067/luca-ferrari/raku/ch-1.p6
@@ -12,31 +12,15 @@ sub MAIN( Int :$m where { $m > 2 }  = 5,
     # found combinations
     my @combinations;
 
-    for 0 ..^ $m {
 
-        # cannot get negative numbers!
-        next if $m - $_ < $n;
-
-        # current combination
-        my @combination;
-        # push the last digit of this combination, for example m=5, n=3 -> 5
-        @combination.push: $m - $_;
-
-        # fill up the combination with decreasing order
-        @combination.push( @combination[ *-1 ] - 1 )  while ( @combination.elems < $n );
-        # push this initial combination, e.g., 5,4,3
-        @combinations.push: Array.new( @combination.reverse );
-
-
-        # now go backwards all the digits until we reach '1' with the last digit
-        # e.g. 5,4,2; 5,4,1
-        while ( @combination[ *-1 ] > 1 ) {
-            @combination[ *-1 ] -= 1;
-            @combinations.push: Array.new( @combination.reverse );
-        }
+    for ( 1 x $n ).Int ^..^ ( $m x $n  ).Int {
+        my @digits = $_.comb;
+        next if @digits.elems != $n;
+        my $ok = True;
+        $ok = False if ( @digits[ $_  ] >= @digits[ $_ + 1 ] ) for 0 ..^ @digits.elems - 1;
+        @combinations.push: @digits if $ok;
     }
 
 
-
     @combinations.sort.join( ", " ).say;
 }
-- 
cgit 


From 9c185dffa7f9568cad642076729b93d3e1011168 Mon Sep 17 00:00:00 2001
From: Luca Ferrari <fluca1978@gmail.com>
Date: Mon, 29 Jun 2020 13:48:10 +0200
Subject: Fix boundaries.

---
 challenge-067/luca-ferrari/raku/ch-1.p6 | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/challenge-067/luca-ferrari/raku/ch-1.p6 b/challenge-067/luca-ferrari/raku/ch-1.p6
index a408701f34..ed10fbdcee 100644
--- a/challenge-067/luca-ferrari/raku/ch-1.p6
+++ b/challenge-067/luca-ferrari/raku/ch-1.p6
@@ -6,7 +6,7 @@
 # Every combination should be sorted i.e. [2,3] is valid combination but [3,2] is not.
 
 
-sub MAIN( Int :$m where { $m > 2 }  = 5,
+sub MAIN( Int :$m where { 10 > $m > 2 }  = 5,
           Int :$n where { $n < $m } = 2 ) {
 
     # found combinations
@@ -16,6 +16,7 @@ sub MAIN( Int :$m where { $m > 2 }  = 5,
     for ( 1 x $n ).Int ^..^ ( $m x $n  ).Int {
         my @digits = $_.comb;
         next if @digits.elems != $n;
+        next if @digits.grep( * > $m );
         my $ok = True;
         $ok = False if ( @digits[ $_  ] >= @digits[ $_ + 1 ] ) for 0 ..^ @digits.elems - 1;
         @combinations.push: @digits if $ok;
-- 
cgit