Day 7

d07/main.py

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+from collections import Counter
+from enum import auto
+from enum import Enum
+from enum import StrEnum
+from pathlib import Path
+
+
+FACE_VALUES = {
+    "A": 14,
+    "K": 13,
+    "Q": 12,
+    "J": 11,
+    "T": 10,
+}
+
+
+def card_value(card: str) -> int:
+    if card.isnumeric():
+        return int(card)
+
+    return FACE_VALUES[card]
+
+
+class HandType(Enum):
+    HIGH_CARD = auto()
+    ONE_PAIR = auto()
+    TWO_PAIR = auto()
+    THREE_OF_A_KIND = auto()
+    FULL_HOUSE = auto()
+    FOUR_OF_A_KIND = auto()
+    FIVE_OF_A_KIND = auto()
+
+
+class Hand:
+    def __init__(self, cards: str, bid: int, use_jokers=False):
+        self.cards = cards
+        self.bid = bid
+
+        self.hand_type: HandType = HandType.HIGH_CARD
+
+        counts = Counter(self.cards)
+        jokers = counts["J"]
+
+        for card, count in counts.most_common():
+            if count == 5 or (use_jokers and card != "J" and count + jokers >= 5):
+                self.hand_type = HandType.FIVE_OF_A_KIND
+                if count != 5:
+                    jokers -= 5 - count
+                break
+            # It's always better to use the jokers to improve a hand
+            if use_jokers and card == "J":
+                continue
+            if count == 4 or count + jokers >= 4:
+                self.hand_type = HandType.FOUR_OF_A_KIND
+                if count != 4:
+                    jokers -= 4 - count
+                break
+            if count == 3 or count + jokers >= 3:
+                if self.hand_type == HandType.HIGH_CARD:
+                    self.hand_type = HandType.THREE_OF_A_KIND
+                elif self.hand_type == HandType.ONE_PAIR:
+                    self.hand_type = HandType.FULL_HOUSE
+                if count != 3:
+                    jokers -= 3 - count
+                continue
+            if count == 2 or count + jokers >= 2:
+                if self.hand_type == HandType.HIGH_CARD:
+                    self.hand_type = HandType.ONE_PAIR
+                elif self.hand_type == HandType.ONE_PAIR:
+                    self.hand_type = HandType.TWO_PAIR
+                elif self.hand_type == HandType.THREE_OF_A_KIND:
+                    self.hand_type = HandType.FULL_HOUSE
+                if count != 2:
+                    jokers -= 2 - count
+                continue
+
+    def __lt__(self, other: "Hand") -> bool:
+        # print(f"Comparing {self} to {other}")
+        if self.hand_type == other.hand_type:
+            for s, o in zip(self.cards, other.cards):
+                if s != o:
+                    return card_value(s) < card_value(o)
+
+        return self.hand_type.value < other.hand_type.value
+
+    def __repr__(self) -> str:
+        return f"<{self.cards} {self.bid}: {self.hand_type}>"
+
+
+def part1(input: Path) -> int:
+    hands: list[Hand] = []
+    with input.open() as f:
+        for line in f:
+            line = line.strip()
+            parts = line.partition(" ")
+            hands.append(Hand(parts[0], int(parts[2])))
+
+    answer = 0
+    for i, hand in enumerate(sorted(hands)):
+        print(hand)
+        answer += (i + 1) * hand.bid
+
+    return answer
+
+
+def part2(input: Path) -> int:
+    FACE_VALUES["J"] = 1
+
+    hands: list[Hand] = []
+    with input.open() as f:
+        for line in f:
+            line = line.strip()
+            parts = line.partition(" ")
+            hands.append(Hand(parts[0], int(parts[2]), use_jokers=True))
+
+    answer = 0
+    for i, hand in enumerate(sorted(hands)):
+        print(hand)
+        answer += (i + 1) * hand.bid
+
+    return answer
+
+
+if __name__ == "__main__":
+    input = Path("input.txt")
+    # input = Path("sub-test.txt")
+    # input = Path("sample.txt")
+    result1 = part1(input)
+    print("part1", result1)
+
+    result2 = part2(input)
+    print("part2", result2)

d07/sample.txt

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+32T3K 765
+T55J5 684
+KK677 28
+KTJJT 220
+QQQJA 483

d07/sub-test.txt

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+Q76JJ 123