2023.07

Squashed commit of the following:

commit b15750b28c94f534a9a775112b961bdd9cecfde9
Author: AKP <abi@tdpain.net>
Date:   Thu Dec 7 16:55:14 2023 +0000

    Update `README.md`

commit baa6132676ad52a403fe8119cb829f3a9219691a
Author: AKP <abi@tdpain.net>
Date:   Thu Dec 7 16:53:55 2023 +0000

    Oh cool this works

commit 30b802851ae541e5354bc07806d9d576c5990bb5
Author: AKP <abi@tdpain.net>
Date:   Thu Dec 7 16:37:09 2023 +0000

    This kind of works

challenges/2023/07-camelCards/README.md

@@ -0,0 +1 @@
+# [Day 7: Camel Cards](https://adventofcode.com/2023/day/7)

challenges/2023/07-camelCards/main.py

@@ -0,0 +1,146 @@
+import sys
+from enum import IntEnum
+import functools
+from typing import Callable, Optional
+
+
+def parse(instr: str) -> list[tuple[str, int]]:
+    return [((sp := x.split(" "))[0], int(sp[1])) for x in instr.splitlines()]
+
+
+def count_chars(x: str) -> dict[str, int]:
+    res = {}
+    for ch in x:
+        res[ch] = res.get(ch, 0) + 1
+    return res
+
+
+class HandType(IntEnum):
+    HighCard = 1
+    OnePair = 2
+    TwoPair = 3
+    ThreeOfAKind = 4
+    FullHouse = 5
+    FourOfAKind = 6
+    FiveOfAKind = 7
+
+
+def get_hand_type(hand: str, counts: Optional[dict[str, int]] = None) -> HandType:
+    if counts is None:
+        counts = count_chars(hand)
+    num_unique_chars = len(counts)
+
+    if num_unique_chars == 5:
+        return HandType.HighCard
+
+    if num_unique_chars == 4:
+        return HandType.OnePair
+
+    if num_unique_chars == 1:
+        return HandType.FiveOfAKind
+
+    sorted_counts = list(sorted(counts.values()))
+
+    if num_unique_chars == 3:
+        if sorted_counts == [1, 2, 2]:
+            return HandType.TwoPair
+        return HandType.ThreeOfAKind
+
+    if num_unique_chars == 2:
+        if sorted_counts == [1, 4]:
+            return HandType.FourOfAKind
+        return HandType.FullHouse
+
+    raise ValueError(f"bad hand {hand}")
+
+
+def get_best_hand_type(hand: str) -> HandType:
+    counts = count_chars(hand)
+
+    if "J" in counts:
+        num_jokers = counts["J"]
+
+        if num_jokers == 5:
+            return HandType.FiveOfAKind
+
+        del counts["J"]
+        most_frequent_card = max(counts, key=lambda x: counts[x])
+        counts[most_frequent_card] = counts[most_frequent_card] + num_jokers
+
+    return get_hand_type(hand, counts=counts)
+
+
+def compare_card(a: str, b: str, ranking_sequence: list[str]) -> int:
+    ca, cb = ranking_sequence.index(a), ranking_sequence.index(b)
+
+    if ca > cb:
+        return 1
+
+    if ca < cb:
+        return -1
+
+    return 0
+
+
+def compare_hands(
+    a: str, b: str, ranking_sequence: list[str], hand_type: Callable[[str], HandType]
+) -> int:
+    hta, htb = hand_type(a), hand_type(b)
+
+    if hta > htb:
+        return 1
+
+    if hta < htb:
+        return -1
+
+    for (ca, cb) in zip(a, b):
+        if ca != cb:
+            return compare_card(ca, cb, ranking_sequence)
+
+    return 0
+
+
+def run(
+    instr: str, sequence: list[str], hand_type_fn: Callable[[str], HandType]
+) -> int:
+    @functools.cmp_to_key
+    def cmp_fn(a: tuple[str, any], b: tuple[str, any]) -> int:
+        return compare_hands(a[0], b[0], sequence, hand_type_fn)
+
+    plays = parse(instr)
+    acc = 0
+    for i, (_, bid) in enumerate(sorted(plays, key=cmp_fn)):
+        acc += bid * (i + 1)
+    return acc
+
+
+def one(instr: str):
+    return run(
+        instr,
+        ["2", "3", "4", "5", "6", "7", "8", "9", "T", "J", "Q", "K", "A"],
+        get_hand_type,
+    )
+
+
+def two(instr: str):
+    return run(
+        instr,
+        ["J", "2", "3", "4", "5", "6", "7", "8", "9", "T", "Q", "K", "A"],
+        get_best_hand_type,
+    )
+
+
+def _debug(*args, **kwargs):
+    kwargs["file"] = sys.stderr
+    print(*args, **kwargs)
+
+
+if __name__ == "__main__":
+    if len(sys.argv) < 2 or sys.argv[1] not in ["1", "2"]:
+        print("Missing day argument", file=sys.stderr)
+        sys.exit(1)
+    inp = sys.stdin.read().strip()
+    if sys.argv[1] == "1":
+        print(one(inp))
+    else:
+        print(two(inp))

challenges/2023/07-camelCards/tests.json

@@ -0,0 +1,8 @@
+{
+    "1": [
+        {"is": "6440", "input": "32T3K 765\nT55J5 684\nKK677 28\nKTJJT 220\nQQQJA 483"}
+    ],
+    "2": [
+        {"is": "5905", "input": "32T3K 765\nT55J5 684\nKK677 28\nKTJJT 220\nQQQJA 483"}
+    ]
+}

challenges/2023/README.md

@@ -16,3 +16,4 @@ Solutions to the [2023 Advent of Code](https://adventofcode.com/2023).
 | 04 - Scratchcards | ★ ★ | Python | First flawed initial grok of the year |
 | 05 - If You Give A Seed A Fertilizer | ★ ☆ | Python | This year is ridiculously unbalanced. Why is it so hard already. |
 | 06 - Wait For It | ★ ★ | Python | Easy, GCSE-level maths :) |
+| 07 - Camel Cards | ★ ★ | Python | Pedantic problem statements will be my downfall |