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diff --git a/‎src/advent_of_code/y2023/d4.py
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+import math
+from dataclasses import dataclass
+
+from advent_of_code.util import format_solution, puzzle_input
+
+
+@dataclass
+class ScratchCard:
+    #: Card number
+    number: int
+
+    winning_numbers: set[int]
+
+    your_numbers: set[int]
+
+    def points_value(self):
+        matches = len(self.winning_numbers & self.your_numbers)
+        return int(math.pow(2, matches - 1)) if matches > 0 else 0
+
+    def card_winnings(self) -> list[int]:
+        matches = len(self.winning_numbers & self.your_numbers)
+        return [self.number + i + 1 for i in range(matches)]
+
+
+def parse_card(card: str) -> ScratchCard:
+    card_info, nums_part = card.split(":")
+    card_num = int(card_info.split("Card")[1].strip())
+
+    winning_nums_part, your_nums_part = nums_part.split("|")
+
+    winning_nums = {int(n.strip()) for n in winning_nums_part.split(" ") if len(n) > 0}
+    your_nums = {int(n.strip()) for n in your_nums_part.split(" ") if len(n) > 0}
+
+    return ScratchCard(
+        number=card_num,
+        winning_numbers=winning_nums,
+        your_numbers=your_nums,
+    )
+
+
+def part_1(cards_input: list[str]) -> int:
+    cards = [parse_card(line) for line in cards_input]
+
+    return sum(card.points_value() for card in cards)
+
+
+def part_2(cards_input: list[str]) -> int:
+    cards = sorted([parse_card(line) for line in cards_input], key=lambda c: c.number)
+
+    card_counts = {card.number: 1 for card in cards}
+
+    for card in cards:
+        for new_card_num in card.card_winnings():
+            card_counts[new_card_num] += card_counts[card.number]
+
+    return sum(card_counts.values())
+
+
+if __name__ == "__main__":
+    puzzle = puzzle_input(2023, 4)
+
+    print(
+        format_solution(
+            solver_p1=lambda: part_1(puzzle),
+            solver_p2=lambda: part_2(puzzle),
+        )
+    )