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+--- Day 23: Coprocessor Conflagration ---
+
+You decide to head directly to the CPU and fix the printer from there.
+As you get close, you find an experimental coprocessor doing so much
+work that the local programs are afraid it will halt and catch fire.
+This would cause serious issues for the rest of the computer, so you
+head in and see what you can do.
+
+The code it's running seems to be a variant of the kind you saw
+recently on that tablet. The general functionality seems very similar,
+but some of the instructions are different:
+
+    set X Y sets register X to the value of Y.
+
+    sub X Y decreases register X by the value of Y.
+
+    mul X Y sets register X to the result of multiplying the value
+    contained in register X by the value of Y.
+
+    jnz X Y jumps with an offset of the value of Y, but only if the
+    value of X is not zero. (An offset of 2 skips the next
+    instruction, an offset of -1 jumps to the previous instruction,
+    and so on.)
+
+    Only the instructions listed above are used. The eight registers
+    here, named a through h, all start at 0.
+
+The coprocessor is currently set to some kind of debug mode, which
+allows for testing, but prevents it from doing any meaningful work.
+
+If you run the program (your puzzle input), how many times is the mul
+instruction invoked?
+
+Your puzzle answer was 3025.
+
+--- Part Two ---
+
+Now, it's time to fix the problem.
+
+The debug mode switch is wired directly to register a. You flip the
+switch, which makes register a now start at 1 when the program is
+executed.
+
+Immediately, the coprocessor begins to overheat. Whoever wrote this
+program obviously didn't choose a very efficient implementation.
+You'll need to optimize the program if it has any hope of completing
+before Santa needs that printer working.
+
+The coprocessor's ultimate goal is to determine the final value left
+in register h once the program completes. Technically, if it had
+that... it wouldn't even need to run the program.
+
+After setting register a to 1, if the program were to run to
+completion, what value would be left in register h?
+
+Your puzzle answer was 915.
+
+Both parts of this puzzle are complete! They provide two gold stars: **