Poetry stuff.

src/holt59/aoc/2022/day13.py

@@ -0,0 +1,41 @@
+import json
+import sys
+from functools import cmp_to_key
+from typing import TypeAlias, cast
+
+blocks = sys.stdin.read().strip().split("\n\n")
+
+pairs = [tuple(json.loads(p) for p in block.split("\n")) for block in blocks]
+
+Packet: TypeAlias = list[int | list["Packet"]]
+
+
+def compare(lhs: Packet, rhs: Packet) -> int:
+    for lhs_a, rhs_a in zip(lhs, rhs):
+        if isinstance(lhs_a, int) and isinstance(rhs_a, int):
+            if lhs_a != rhs_a:
+                return rhs_a - lhs_a
+        else:
+            if not isinstance(lhs_a, list):
+                lhs_a = [lhs_a]  # type: ignore
+            elif not isinstance(rhs_a, list):
+                rhs_a = [rhs_a]  # type: ignore
+            assert isinstance(rhs_a, list) and isinstance(lhs_a, list)
+            r = compare(cast(Packet, lhs_a), cast(Packet, rhs_a))
+            if r != 0:
+                return r
+
+    return len(rhs) - len(lhs)
+
+
+answer_1 = sum(i + 1 for i, (lhs, rhs) in enumerate(pairs) if compare(lhs, rhs) > 0)
+print(f"answer_1 is {answer_1}")
+
+dividers = [[[2]], [[6]]]
+
+packets = [packet for packets in pairs for packet in packets]
+packets.extend(dividers)
+packets = list(reversed(sorted(packets, key=cmp_to_key(compare))))
+
+d_index = [packets.index(d) + 1 for d in dividers]
+print(f"answer 2 is {d_index[0] * d_index[1]}")