2022-13

Author: viliampucik

2022/13.py

@@ -0,0 +1,42 @@
+#!/usr/bin/env python
+from math import prod
+from functools import cmp_to_key
+
+
+def cmp(left, right):
+    match left, right:
+        case int(), list():
+            return cmp([left], right)
+        case list(), int():
+            return cmp(left, [right])
+        case int(), int():
+            return left - right
+        case list(), list():
+            for i, j in zip(left, right):
+                if (r := cmp(i, j)) != 0:
+                    return r
+            return cmp(len(left), len(right))
+
+
+# fmt: off
+packets = [
+    eval(line)
+    for line in open(0).read().splitlines()
+    if len(line)
+]
+
+print(sum(
+    i
+    for i, (left, right) in enumerate(zip(packets[::2], packets[1::2]), start=1)
+    if cmp(left, right) <= 0
+))
+
+two_six = [[[2]], [[6]]]
+print(prod(
+    i
+    for i, packet in enumerate(
+        sorted(packets + two_six, key=cmp_to_key(cmp)),
+        start=1
+    )
+    if packet in two_six
+))