1 files changed, 28 insertions, 0 deletions
diff --git a/16/a.rb b/16/a.rb
new file mode 100644
index 0000000..dd3eea4
--- /dev/null
+++ b/16/a.rb
@@ -0,0 +1,28 @@
+sections = File.read('input.txt').split "\n\n"
+
+fields = sections[0].split "\n"
+tickets = sections[2].split "\n"
+
+valid_values = Hash.new false
+
+fields.each do |field|
+  ranges = field.split(/.*: | or /).slice(1, 2)
+  ranges.each do |range|
+    from, to = range.split('-').map {|n| n.to_i}
+    (from..to).each do |n|
+      valid_values[n] = true
+    end
+  end
+end
+
+invalid = 0
+tickets.each do |ticket|
+  values = ticket.split(',').map {|n| n.to_i}
+  values.each do |n|
+    if !valid_values[n]
+      invalid += n
+    end
+  end
+end
+
+puts invalid