From 752998b08a702de0d0dae222f49f264e83f0dee3 Mon Sep 17 00:00:00 2001
From: mid-kid <esteve.varela@gmail.com>
Date: Fri, 21 Dec 2018 14:34:39 +0100
Subject: [PATCH] Improve day21p2

Should now properly handle all inputs
---
 day21p2/main.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/day21p2/main.c b/day21p2/main.c
index 8d243b2..f50e8a2 100644
--- a/day21p2/main.c
+++ b/day21p2/main.c
@@ -177,10 +177,15 @@ int main(int argc, char *argv[])
     while (regs[ip] >= 0 && regs[ip] < instructions_len) {
         struct instr *instr = &instructions[regs[ip]];
 
-        // Day 21 part 2 optimizations...
-        if (regs[ip] == 17) {
-            regs[5] >>= 8;
-            regs[ip] = 8;
+        // Day 21 part 2 optimization...
+        if (instr->i == INSTR_GTIR && instr->a == 0x100) {
+            reg_t *reg = &regs[instr->b];
+            if (0x100 <= *reg) {
+                *reg >>= 8;
+                regs[ip] = 8;
+            } else {
+                regs[ip] = 28;
+            }
             continue;
         }