Add day 5

2 files changed, 26 insertions, 0 deletions

diff --git a/05/a.rb b/05/a.rb
new file mode 100644
index 0000000..877abb9
--- /dev/null
+++ b/05/a.rb
@@ -0,0 +1,11 @@
+max = 0
+File.readlines('input.txt').map do |line|
+  line.tr('FBLR', '0101')
+end.each do |line|
+  row = line.slice(0, 7).to_i 2
+  seat = line.slice(7, 3).to_i 2
+  id = row * 8 + seat
+  max = [id, max].max
+end
+
+puts max
diff --git a/05/b.rb b/05/b.rb
new file mode 100644
index 0000000..378f7c6
--- /dev/null
+++ b/05/b.rb
@@ -0,0 +1,15 @@
+missing = 0
+File.readlines('input.txt').map do |line|
+  line.tr('FBLR', '0101')
+end.map do |line|
+  row = line.slice(0, 7).to_i 2
+  seat = line.slice(7, 3).to_i 2
+  row * 8 + seat
+end.sort.reduce do |last_seen, current|
+  if current - 1 != last_seen
+    missing = current - 1
+  end
+  current
+end
+
+puts missing