1 files changed, 51 insertions, 0 deletions
diff --git a/day10/part1.rb b/day10/part1.rb
new file mode 100644
index 0000000..dfad57e
--- /dev/null
+++ b/day10/part1.rb
@@ -0,0 +1,51 @@
+class CPU
+  def initialize
+    @x = 1
+    @cycle = 1
+    @iq = []
+  end
+
+  attr_reader :x, :cycle
+
+  def enq(op, arg = 0)
+    @iq << [
+      arg,
+      case op
+      when 'noop'; 1
+      when 'addx'; 2
+      end
+    ]
+  end
+
+  def done?
+    @iq.empty?
+  end
+
+  def clock
+    istr = @iq[0]
+    istr[1] -= 1
+    if istr[1] == 0
+      @x += istr[0]
+      @iq.shift
+    end
+    @cycle += 1
+  end
+end
+
+cpu = CPU.new
+
+istrs = $stdin.readlines.map(&:strip).map(&:split)
+istrs.each do |istr|
+  cpu.enq(istr[0], istr[1]&.to_i || 0)
+end
+
+strsum = 0
+until cpu.done?
+  c = cpu.cycle
+  x = cpu.x
+
+  strsum += (c * x) if (c - 20) % 40 == 0
+  cpu.clock
+end
+
+puts strsum