From faa90e31db32bf327a43f0d1761bdc0b7e18edae Mon Sep 17 00:00:00 2001
From: Kang-min Liu <gugod@gugod.org>
Date: Tue, 24 Nov 2020 10:10:18 +0900
Subject: @gugod's solution to pwc 088.2

---
 challenge-088/gugod/raku/ch-2.raku | 77 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 77 insertions(+)
 create mode 100644 challenge-088/gugod/raku/ch-2.raku

diff --git a/challenge-088/gugod/raku/ch-2.raku b/challenge-088/gugod/raku/ch-2.raku
new file mode 100644
index 0000000000..48f999db52
--- /dev/null
+++ b/challenge-088/gugod/raku/ch-2.raku
@@ -0,0 +1,77 @@
+my @directions = [
+    [ 1, 0],  # →
+    [ 0, 1],  # ↓
+    [-1, 0],  # ←
+    [ 0,-1],  # ↑
+];
+
+sub turn ($curdir is rw, @boundary) of Nil  { # ⤵
+    @boundary[$curdir] += ($curdir == 0|3) ?? 1 !! -1;
+    $curdir = ($curdir + 1) % 4;
+    return;
+}
+
+sub next-step (@cursor, $curdir) {
+    @cursor >>+<< @directions[$curdir];
+}
+
+sub inside-boundary(@cursor, @boundary) of Bool {
+    return ((@boundary[3] < @cursor[0] < @boundary[1])
+            and (@boundary[0] < @cursor[1] < @boundary[2]));
+}
+
+sub spiral-matrix (@M) {
+    my $width = @M[0].elems;
+    my $height = @M.elems;
+    my @cursor = [0,0];
+
+    # The index here is arranged in thee way to make it easier to implement turn().
+    my $curdir = 0;
+    my @boundary = [
+        -1,      # ↑
+        $width,  # →
+        $height, # ↓
+        -1,      # ←
+    ];
+
+    my @spiral;
+    while inside-boundary(@cursor, @boundary) {
+        @spiral.push(@M[@cursor[1]][@cursor[0]]);
+
+        my @next = next-step(@cursor, $curdir);
+        unless inside-boundary(@next, @boundary) {
+            turn($curdir, @boundary);
+            @next = next-step(@cursor, $curdir);
+        }
+
+        @cursor = @next;
+    }
+
+    return @spiral;
+}
+
+sub print-matrix(@matrix) {
+    for ^@matrix -> $y {
+        say "[" ~ @matrix[$y].map(-> $it { sprintf("%2d", $it) }).join(" ") ~ "]";
+    }
+}
+
+my @examples = (
+    [[1,2],
+     [3,4]],
+    [[1,2,3],
+     [4,5,6]],
+    [[1,2,3],
+     [4,5,6],
+     [7,8,9]],
+    [[1,2,3],
+     [4,5,6],
+     [7,8,9],
+     [10,11,12],],
+);
+
+for @examples -> @M {
+    say "----\nInput: ";
+    print-matrix(@M);
+    say "Output: " ~ spiral-matrix(@M).gist;
+}
-- 
cgit 


From bbf75140ed797dd1a263413258ce376022ae952a Mon Sep 17 00:00:00 2001
From: Kang-min Liu <gugod@gugod.org>
Date: Tue, 24 Nov 2020 18:09:15 +0900
Subject: add a test case

---
 challenge-088/gugod/raku/ch-2.raku | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/challenge-088/gugod/raku/ch-2.raku b/challenge-088/gugod/raku/ch-2.raku
index 48f999db52..b630611493 100644
--- a/challenge-088/gugod/raku/ch-2.raku
+++ b/challenge-088/gugod/raku/ch-2.raku
@@ -64,6 +64,10 @@ my @examples = (
     [[1,2,3],
      [4,5,6],
      [7,8,9]],
+    [[  1,  2,  3,  4 ],
+     [  5,  6,  7,  8 ],
+     [  9, 10, 11, 12 ],
+     [ 13, 14, 15, 16 ]],
     [[1,2,3],
      [4,5,6],
      [7,8,9],
-- 
cgit 


From 5389f71ab4b021f54bebce65de9002c403b81cad Mon Sep 17 00:00:00 2001
From: Kang-min Liu <gugod@gugod.org>
Date: Tue, 24 Nov 2020 18:19:50 +0900
Subject: add a naive solution for 088.1

---
 challenge-088/gugod/raku/ch-1.raku | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 challenge-088/gugod/raku/ch-1.raku

diff --git a/challenge-088/gugod/raku/ch-1.raku b/challenge-088/gugod/raku/ch-1.raku
new file mode 100644
index 0000000000..a5723ffb40
--- /dev/null
+++ b/challenge-088/gugod/raku/ch-1.raku
@@ -0,0 +1,16 @@
+sub array-of-product (@N) {
+    my $p = [*] @N;
+    return @N.map(-> $n { $p / $n });
+}
+
+my @examples = [
+    [5, 2, 1, 4, 3],
+    [2, 1, 4, 3],
+    [1, 3, 3, 7],
+];
+
+for @examples -> @N {
+    say "Input  @N = { @N.gist }";
+    say "Output @M = " ~ array-of-product(@N).gist;
+    say "----";
+}
-- 
cgit 


From cb8e9359613d4b55fe20222f3ca1975d3c362e1e Mon Sep 17 00:00:00 2001
From: Kang-min Liu <gugod@gugod.org>
Date: Tue, 24 Nov 2020 19:01:43 +0900
Subject: put everything in the same subroutine.

---
 challenge-088/gugod/raku/ch-2.raku | 72 ++++++++++++++++++++------------------
 1 file changed, 37 insertions(+), 35 deletions(-)

diff --git a/challenge-088/gugod/raku/ch-2.raku b/challenge-088/gugod/raku/ch-2.raku
index b630611493..e5a21065b7 100644
--- a/challenge-088/gugod/raku/ch-2.raku
+++ b/challenge-088/gugod/raku/ch-2.raku
@@ -1,32 +1,20 @@
-my @directions = [
-    [ 1, 0],  # →
-    [ 0, 1],  # ↓
-    [-1, 0],  # ←
-    [ 0,-1],  # ↑
-];
-
-sub turn ($curdir is rw, @boundary) of Nil  { # ⤵
-    @boundary[$curdir] += ($curdir == 0|3) ?? 1 !! -1;
-    $curdir = ($curdir + 1) % 4;
-    return;
-}
-
-sub next-step (@cursor, $curdir) {
-    @cursor >>+<< @directions[$curdir];
-}
-
-sub inside-boundary(@cursor, @boundary) of Bool {
-    return ((@boundary[3] < @cursor[0] < @boundary[1])
-            and (@boundary[0] < @cursor[1] < @boundary[2]));
-}
 
 sub spiral-matrix (@M) {
-    my $width = @M[0].elems;
-    my $height = @M.elems;
-    my @cursor = [0,0];
+    # Things don'tt change
+    my $width  := @M[0].elems;
+    my $height := @M.elems;
+    my @directions := [
+        [ 1, 0],  # →
+        [ 0, 1],  # ↓
+        [-1, 0],  # ←
+        [ 0,-1],  # ↑
+    ];
 
-    # The index here is arranged in thee way to make it easier to implement turn().
+    # Things change.
+    my @cursor = [0,0];
     my $curdir = 0;
+
+    # The order of boundary is arranged in thee way to make it easier to implement turn().
     my @boundary = [
         -1,      # ↑
         $width,  # →
@@ -34,20 +22,34 @@ sub spiral-matrix (@M) {
         -1,      # ←
     ];
 
-    my @spiral;
-    while inside-boundary(@cursor, @boundary) {
-        @spiral.push(@M[@cursor[1]][@cursor[0]]);
+    my sub turn ($curdir is rw, @boundary) of Nil  { # ⤵
+        @boundary[$curdir] += ($curdir == 0|3) ?? 1 !! -1;
+        $curdir = ($curdir + 1) % 4;
+        return;
+    }
 
-        my @next = next-step(@cursor, $curdir);
-        unless inside-boundary(@next, @boundary) {
-            turn($curdir, @boundary);
-            @next = next-step(@cursor, $curdir);
-        }
+    my sub next-step (@cursor, $curdir) {
+        @cursor >>+<< @directions[$curdir];
+    }
 
-        @cursor = @next;
+    my sub inside-boundary(@cursor, @boundary) of Bool {
+        return ((@boundary[3] < @cursor[0] < @boundary[1])
+                and (@boundary[0] < @cursor[1] < @boundary[2]));
     }
 
-    return @spiral;
+    return gather {
+        while inside-boundary(@cursor, @boundary) {
+            take @M[@cursor[1]][@cursor[0]];
+
+            my @next = next-step(@cursor, $curdir);
+            unless inside-boundary(@next, @boundary) {
+                turn($curdir, @boundary);
+                @next = next-step(@cursor, $curdir);
+            }
+
+            @cursor = @next;
+        }
+    };
 }
 
 sub print-matrix(@matrix) {
-- 
cgit 


From 37e3de628deb7c89e06cb1a0d66d566cca636bda Mon Sep 17 00:00:00 2001
From: Kang-min Liu <gugod@gugod.org>
Date: Wed, 25 Nov 2020 08:32:44 +0900
Subject: links to blog posts.

---
 challenge-088/gugod/README | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/challenge-088/gugod/README b/challenge-088/gugod/README
index 9a4443f23b..552c5afaa1 100644
--- a/challenge-088/gugod/README
+++ b/challenge-088/gugod/README
@@ -1,6 +1,6 @@
 Solutions by Kang-min Liu.
 
 Blog posts:
-- https://gugod.org/2020/11/pwc-087/
-- https://gugod.org/2020/11/pwc-087-en/
-- https://dev.to/gugod/solvintg-perl-weekly-challenge-087-1f09
+- https://gugod.org/2020/11/pwc-088/
+- https://gugod.org/2020/11/pwc-088-en/
+- https://dev.to/gugod/solving-perl-weekly-challenge-088-array-of-prodict-vs-spiral-matrix-13ni
-- 
cgit 


From 551f1b6fa8dd268f4fecbd81a96663ba0a632a17 Mon Sep 17 00:00:00 2001
From: Kang-min Liu <gugod@gugod.org>
Date: Sun, 29 Nov 2020 18:23:35 +0900
Subject: links to blog posts.

---
 challenge-088/gugod/blog.txt | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 challenge-088/gugod/blog.txt

diff --git a/challenge-088/gugod/blog.txt b/challenge-088/gugod/blog.txt
new file mode 100644
index 0000000000..d53d5d2b59
--- /dev/null
+++ b/challenge-088/gugod/blog.txt
@@ -0,0 +1 @@
+https://gugod.org/2020/11/pwc-088-en/
-- 
cgit 


From 1aaeb59f9d845cf891e81e9e96ba414b8fedbc8f Mon Sep 17 00:00:00 2001
From: Kang-min Liu <gugod@gugod.org>
Date: Sun, 29 Nov 2020 19:13:59 +0900
Subject: task 1: handle the case when there are zeros.

---
 challenge-088/gugod/raku/ch-1.raku | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/challenge-088/gugod/raku/ch-1.raku b/challenge-088/gugod/raku/ch-1.raku
index a5723ffb40..43e8b650fd 100644
--- a/challenge-088/gugod/raku/ch-1.raku
+++ b/challenge-088/gugod/raku/ch-1.raku
@@ -1,12 +1,27 @@
 sub array-of-product (@N) {
-    my $p = [*] @N;
-    return @N.map(-> $n { $p / $n });
+    my $zeros = @N.grep(-> $n { $n == 0 }).elems;
+
+    my $q = [*] @N.grep(-> $n { $n != 0 });
+
+    my $fun;
+
+    if $zeros == 0 {
+        $fun = -> $n { $q / $n };
+    } elsif $zeros == 1 {
+        $fun = -> $n { $n == 0 ?? $q !! 0 };
+    } else {
+        $fun = -> $n { 0 };
+    }
+
+    return @N.map($fun);
 }
 
 my @examples = [
     [5, 2, 1, 4, 3],
     [2, 1, 4, 3],
     [1, 3, 3, 7],
+    [1, 3, 0, 3, 7],
+    [1, 3, 0, 3, 7, 0],
 ];
 
 for @examples -> @N {
-- 
cgit