Merge pull request #3942 from brtastic/challenge-109

Challenge 109 solutions by brtastic

6 files changed, 167 insertions, 0 deletions

diff --git a/challenge-109/brtastic/perl/ch-1.pl b/challenge-109/brtastic/perl/ch-1.pl
new file mode 100644
index 0000000000..5e39abfbe3
--- /dev/null
+++ b/challenge-109/brtastic/perl/ch-1.pl
@@ -0,0 +1,9 @@
+use v5.30;
+use warnings;
+use List::Util qw(sum0);
+
+for my $num (1 .. 20) {
+	say sum0 grep {
+		$num % $_ == 0
+	} 2 .. int($num / 2);
+}
diff --git a/challenge-109/brtastic/perl/ch-2.pl b/challenge-109/brtastic/perl/ch-2.pl
new file mode 100644
index 0000000000..d777e956b5
--- /dev/null
+++ b/challenge-109/brtastic/perl/ch-2.pl
@@ -0,0 +1,52 @@
+use v5.30;
+use warnings;
+use List::Util qw(all sum0);
+
+use constant EL_COUNT => 7;
+
+sub permute
+{
+	my (@what) = @_;
+
+	return [@what] if @what == 1;
+
+	my @options;
+
+	for my $el (@what) {
+		my $seen = 0;
+		push @options, map {
+			[$el, @$_]
+		} permute(grep {
+			$_ != $el || $seen++
+		} @what);
+	}
+
+	return @options;
+}
+
+sub four_squares
+{
+	my (@input) = @_;
+	my @results;
+
+	return @results if @input != EL_COUNT;
+
+	for my $case (permute @input) {
+		my @real_case = (0, @$case, 0);
+		my @summed_groups = map {
+			sum0 map { $real_case[$_] } $_ .. $_ + 2
+		} grep {
+			$_ % 2 == 0 && $_ <= @real_case - 2
+		} keys @real_case;
+
+		my $letter = 'a';
+		push @results, {map { $letter++, $_ } @$case}
+			if all { $_ == @summed_groups[0] } @summed_groups;
+	}
+
+	return @results;
+}
+
+use Data::Dumper;
+say Dumper([four_squares 1 .. 7]);
+
diff --git a/challenge-109/brtastic/php/ch-1.php b/challenge-109/brtastic/php/ch-1.php
new file mode 100644
index 0000000000..cc5c5e6de3
--- /dev/null
+++ b/challenge-109/brtastic/php/ch-1.php
@@ -0,0 +1,8 @@
+<?php
+
+foreach(range(1, 20) as $num) {
+	echo array_sum(array_filter(
+		$num >= 4 ? range(2, floor($num / 2)) : [],
+		fn ($divisor) => $num % $divisor == 0
+	)) . "\n";
+}
diff --git a/challenge-109/brtastic/php/ch-2.php b/challenge-109/brtastic/php/ch-2.php
new file mode 100644
index 0000000000..304967ffae
--- /dev/null
+++ b/challenge-109/brtastic/php/ch-2.php
@@ -0,0 +1,75 @@
+<?php
+
+const EL_COUNT = 7;
+
+function permute($what)
+{
+	if (count($what) == 1) {
+		return [$what];
+	}
+
+	$options = [];
+
+	foreach($what as $el) {
+		$seen = 0;
+		array_push($options, ...array_map(
+			fn ($arr) => [$el, ...$arr],
+			permute(
+				array_filter(
+					$what,
+					fn ($subel)
+						=> $subel != $el || $seen++
+				)
+			)
+		));
+	}
+
+	return $options;
+}
+
+function four_squares($input)
+{
+	$results = [];
+
+	if (count($input) != EL_COUNT) {
+		return $results;
+	}
+
+	foreach (permute($input) as $case) {
+		$real_case = [0, ...$case, 0];
+		$summed_groups = array_map(
+			fn ($el)
+				=> array_sum(
+					array_map(
+						fn ($subel)
+							=> $real_case[$subel],
+					range($el, $el + 2))
+				),
+			array_filter(
+				array_keys($real_case),
+				fn ($el)
+					=> $el % 2 == 0 && $el <= count($real_case) - 2
+			)
+		);
+
+		$matching_first = array_filter(
+			$summed_groups,
+			fn ($el)
+				=> $el == $summed_groups[0]
+		);
+
+		if (count($matching_first) == count($summed_groups)) {
+			$case_results = [];
+			for ($letter = 'a'; $letter != 'h'; ++$letter) {
+				$case_results[$letter] = array_shift($case);
+			}
+
+			$results[] = $case_results;
+		}
+	}
+
+	return $results;
+}
+
+var_dump(four_squares(range(1, 7)));
+
diff --git a/challenge-109/brtastic/raku/ch-1.raku b/challenge-109/brtastic/raku/ch-1.raku
new file mode 100644
index 0000000000..fab08a6c80
--- /dev/null
+++ b/challenge-109/brtastic/raku/ch-1.raku
@@ -0,0 +1,7 @@
+for 1 .. 20 -> $num {
+	say [+] gather {
+		for 1 ^.. ($num / 2).truncate -> $divisor {
+			take $divisor if $num %% $divisor;
+		}
+	}
+}
diff --git a/challenge-109/brtastic/raku/ch-2.raku b/challenge-109/brtastic/raku/ch-2.raku
new file mode 100644
index 0000000000..2495669858
--- /dev/null
+++ b/challenge-109/brtastic/raku/ch-2.raku
@@ -0,0 +1,16 @@
+constant $el-count = 7;
+
+sub four-squares(@input where .elems == $el-count --> Array[Map])
+{
+	my Map @results;
+	for @input.permutations -> @case {
+		my @sum_groups = (0, |@case, 0).rotor(3 => -1);
+
+		@results.push: %(flat zip 'a' .. 'g', @case)
+			if [==] @sum_groups.map: { [+] $_ };
+	}
+
+	return @results;
+}
+
+say four-squares 1 .. 7;