From 63b534141e63cf51990d5fa2234e1d21f0bc1bbc Mon Sep 17 00:00:00 2001
From: "Jan \"Yenya\" Kasprzak" <kas@fi.muni.cz>
Date: Mon, 21 Dec 2020 09:09:50 +0100
Subject: [PATCH] Day 21

---
 41.pl | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 42.pl | 42 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 88 insertions(+)
 create mode 100755 41.pl
 create mode 100755 42.pl

diff --git a/41.pl b/41.pl
new file mode 100755
index 0000000..846f78e
--- /dev/null
+++ b/41.pl
@@ -0,0 +1,46 @@
+#!/usr/bin/perl -w
+
+use strict;
+
+my %allergens;
+my %ingredients;
+my %in_count;
+
+while (<>) {
+	chomp;
+	my ($ingr, $al) = /\A([^\(]+) \(contains (.*)\)\z/;
+	my %ingr = map { $_ => 1 } split /\s+/, $ingr;
+	my @al = split /, /, $al;
+	for my $al (@al) {
+		if (defined $allergens{$al}) {
+			for my $in1 (keys %{ $allergens{$al} }) {
+				if (! $ingr{$in1}) {
+					delete $allergens{$al}->{$in1};
+				}
+			}
+		} else {
+			$allergens{$al} = { %ingr };
+		}
+	}
+	for my $in (keys %ingr) {
+		$ingredients{$in} = {};
+		$in_count{$in}++;
+	}
+}
+
+for my $al (keys %allergens) {
+	for my $in (keys %{ $allergens{$al} }) {
+		print "$in can be $al.\n";
+		$ingredients{$in}->{$al} = 1;
+	}
+}
+
+my $sum = 0;
+for my $in (keys %ingredients) {
+	if (keys %{ $ingredients{$in} } == 0) {
+		# print "$in can't contain allergen\n";
+		$sum += $in_count{$in};
+	}
+}
+
+print "Sum=$sum\n";
diff --git a/42.pl b/42.pl
new file mode 100755
index 0000000..05bf2ac
--- /dev/null
+++ b/42.pl
@@ -0,0 +1,42 @@
+#!/usr/bin/perl -w
+
+use strict;
+
+my %allergens;
+my %is_al;
+
+while (<>) {
+	chomp;
+	my ($ingr, $al) = /\A([^\(]+) \(contains (.*)\)\z/;
+	my %ingr = map { $_ => 1 } split /\s+/, $ingr;
+	my @al = split /, /, $al;
+	for my $al (@al) {
+		if (defined $allergens{$al}) {
+			for my $in1 (keys %{ $allergens{$al} }) {
+				if (! $ingr{$in1}) {
+					delete $allergens{$al}->{$in1};
+				}
+			}
+		} else {
+			$allergens{$al} = { %ingr };
+		}
+	}
+}
+
+AGAIN:
+for my $al (keys %allergens) {
+	if (keys %{ $allergens{$al} } == 1) {
+		my $in1;
+		for my $in (keys %{ $allergens{$al} }) {
+			$is_al{$in} = $al;
+			$in1 = $in;
+		}
+		delete $allergens{$al};
+		for my $al1 (keys %allergens) {
+			delete $allergens{$al1}->{$in1};
+		}
+		goto AGAIN;
+	}
+}
+
+print join(',', sort { $is_al{$a} cmp $is_al{$b} } keys %is_al), "\n";
-- 
2.43.0