day 18: now more confusing

1 files changed, 8 insertions, 19 deletions

diff --git a/18.py b/18.py
index 57d06ce..59c3f8a 100644
--- a/18.py
+++ b/18.py
@@ -30,19 +30,14 @@ with open_day(18) as f:
     homework = [parse(l) for l in f]
 
 def try_explode(n):
-    def try_add(n, val, primary, secondary):
+    def try_add(n, val, access, primary, secondary):
         if val == 0: return 0
-        if is_pair(primary(n)):
-            val = try_add(primary(n), val, primary, secondary)
-        else:
-            primary(n, primary(n) + val)
+        content = access(n)
+        if not is_pair(content):
+            access(n, content + val)
             return 0
-        if val != 0:
-            if is_pair(secondary(n)):
-                val = try_add(secondary(n), val, primary, secondary)
-            else:
-                secondary(n, secondary(n) + val)
-                return 0
+        val = try_add(content, val, primary, primary, secondary)
+        val = try_add(content, val, secondary, primary, secondary)
         return val
     def descend(n, depth=0):
         if not is_pair(n): return None
@@ -50,18 +45,12 @@ def try_explode(n):
         car_val = descend(n.car, depth + 1)
         if car_val is not None:
             if depth == 3: n.car = 0
-            if not is_pair(n.cdr):
-                n.cdr += car_val.cdr
-                car_val.cdr = 0
-            return Pair(car_val.car, try_add(n.cdr, car_val.cdr, car, cdr))
+            return Pair(car_val.car, try_add(n, car_val.cdr, cdr, car, cdr))
         else:
             cdr_val = descend(n.cdr, depth + 1)
             if cdr_val is not None:
                 if depth == 3: n.cdr = 0
-                if not is_pair(n.car):
-                    n.car += cdr_val.car
-                    cdr_val.car = 0
-                return Pair(try_add(n.car, cdr_val.car, cdr, car), cdr_val.cdr)
+                return Pair(try_add(n, cdr_val.car, car, cdr, car), cdr_val.cdr)
     return descend(n)
 
 tests = [