Solution to 18.2 in P6 and P5

3 files changed, 184 insertions, 0 deletions

diff --git a/challenge-018/joelle-maslak/perl5/ch-2.pl b/challenge-018/joelle-maslak/perl5/ch-2.pl
new file mode 100755
index 0000000000..e017c62f40
--- /dev/null
+++ b/challenge-018/joelle-maslak/perl5/ch-2.pl
@@ -0,0 +1,57 @@
+#!/usr/bin/env perl
+use v5.22;
+use strict;
+use warnings;
+
+use FindBin;
+use lib "$FindBin::Bin/lib";
+
+# Turn on method signatures
+use feature 'signatures';
+no warnings 'experimental::signatures';
+
+use autodie;
+
+# See lib/PriorityQueue.pm
+use PriorityQueue;
+
+use Test2::V0;
+
+my $pk = PriorityQueue->new();
+
+subtest 'Start empty' => sub {
+    ok $pk->is_empty();
+};
+
+subtest 'One element insert' => sub {
+    $pk->insert_with_priority( 'A', 50 );
+    ok !$pk->is_empty;
+    is $pk->pull_highest_priority_element, 'A';
+    ok $pk->is_empty;
+};
+
+subtest 'With Multiple Priorities' => sub {
+    $pk->insert_with_priority( 'A', 50 );
+    $pk->insert_with_priority( 'B', 50 );
+    $pk->insert_with_priority( 'C', 75 );
+    $pk->insert_with_priority( 'D', 50 );
+    $pk->insert_with_priority( 'E', 10 );
+    $pk->insert_with_priority( 'F', 10 );
+
+    ok !$pk->is_empty;
+    is $pk->pull_highest_priority_element(), 'C';
+
+    $pk->insert_with_priority( 'G', 75 );
+    is $pk->pull_highest_priority_element(), 'G';
+
+    is $pk->pull_highest_priority_element(), 'A';
+    is $pk->pull_highest_priority_element(), 'B';
+    is $pk->pull_highest_priority_element(), 'D';
+    is $pk->pull_highest_priority_element(), 'E';
+    is $pk->pull_highest_priority_element(), 'F';
+
+    ok $pk->is_empty;
+};
+
+done_testing;
+
diff --git a/challenge-018/joelle-maslak/perl5/lib/PriorityQueue.pm b/challenge-018/joelle-maslak/perl5/lib/PriorityQueue.pm
new file mode 100755
index 0000000000..e2e447999e
--- /dev/null
+++ b/challenge-018/joelle-maslak/perl5/lib/PriorityQueue.pm
@@ -0,0 +1,50 @@
+#!/usr/bin/env perl
+use v5.22;
+use strict;
+use warnings;
+
+package PriorityQueue;
+
+use Moose;
+
+# Turn on method signatures
+use feature 'signatures';
+no warnings 'experimental::signatures';
+
+use autodie;
+use List::Util qw(max);
+
+has 'priorities' => (
+    is      => 'rw',
+    isa     => 'HashRef',
+    default => sub { {} },
+);
+
+has 'maxprio' => ( is => 'rw', );
+
+sub is_empty($self) { return !keys $self->priorities->%* }
+
+sub insert_with_priority ( $self, $elem, $priority ) {
+    $self->priorities->{ +$priority } //= [];
+    push $self->priorities->{ +$priority }->@*, $elem;
+
+    if ( ( !defined( $self->maxprio ) ) or ( $priority > $self->maxprio ) ) {
+        $self->maxprio( max keys $self->priorities->%* );
+    }
+
+    return;
+}
+
+sub pull_highest_priority_element($self) {
+    my $elem = shift $self->priorities->{ $self->maxprio }->@*;
+
+    if ( $self->priorities->{ $self->maxprio }->@* == 0 ) {
+        delete $self->priorities->{ $self->maxprio };
+        $self->maxprio( max keys $self->priorities->%* );
+    }
+
+    return $elem;
+}
+
+1;
+
diff --git a/challenge-018/joelle-maslak/perl6/ch-2.p6 b/challenge-018/joelle-maslak/perl6/ch-2.p6
new file mode 100755
index 0000000000..9378f7a9e6
--- /dev/null
+++ b/challenge-018/joelle-maslak/perl6/ch-2.p6
@@ -0,0 +1,77 @@
+#!/usr/bin/env perl6
+use v6;
+
+#
+# Copyright © 2019 Joelle Maslak
+# All Rights Reserved - See License
+#
+
+class Priority-Queue {
+    has %!priorities;
+    has $!max;
+
+    method is_empty() { return ! %!priorities.keys.elems }
+
+    method insert_with_priority($element, $priority) {
+        %!priorities{$priority} //= [];
+        %!priorities{$priority}.push: $element;
+
+        if (! $!max.defined) or ($priority > $!max) {
+            $!max = $priority;
+        }
+    }
+
+    method pull_highest_priority_element() {
+        my $elem = %!priorities{$!max}.shift;
+
+        if %!priorities{$!max}.elems == 0 {
+            %!priorities{$!max}:delete;
+            $!max = %!priorities.keys.max;
+        }
+
+        return $elem;
+    }
+}
+
+sub MAIN() {
+    use Test;
+
+    my $pk = Priority-Queue.new;
+
+    subtest 'Start empty', {
+        is $pk.is_empty, True;
+    }
+
+    subtest 'One element insert', {
+        $pk.insert_with_priority('A', 50);
+        is $pk.is_empty, False;
+        is $pk.pull_highest_priority_element, 'A';
+        is $pk.is_empty, True;
+    }
+
+    subtest 'With Multiple Priorities', {
+        $pk.insert_with_priority('A', 50);
+        $pk.insert_with_priority('B', 50);
+        $pk.insert_with_priority('C', 75);
+        $pk.insert_with_priority('D', 50);
+        $pk.insert_with_priority('E', 10);
+        $pk.insert_with_priority('F', 10);
+
+        is $pk.is_empty, False;
+        is $pk.pull_highest_priority_element, 'C';
+
+        $pk.insert_with_priority('G', 75);
+        is $pk.pull_highest_priority_element, 'G';
+
+        is $pk.pull_highest_priority_element, 'A';
+        is $pk.pull_highest_priority_element, 'B';
+        is $pk.pull_highest_priority_element, 'D';
+        is $pk.pull_highest_priority_element, 'E';
+        is $pk.pull_highest_priority_element, 'F';
+
+        is $pk.is_empty, True;
+    }
+
+    done-testing;
+}
+