Create day22.py

2019/Python/day22.py

@@ -0,0 +1,104 @@
+from enum import Enum
+from typing import Tuple
+
+
+class Command(Enum):
+    CUT = 1
+    INC = 2
+    STA = 4
+
+
+def parse_data() -> list[Tuple[Command, int]]:
+    output = []
+    with open("input.txt") as file:
+        for line in file:
+            line = line.rstrip()
+            if not line:
+                continue
+            elif line[:3] == "cut":
+                output.append((Command.CUT, int(line[3:])))
+            elif line[:19] == "deal with increment":
+                output.append((Command.INC, int(line[19:])))
+            elif line[:19] == "deal into new stack":
+                output.append((Command.STA, 0))
+    return output
+
+
+class Hand:
+    def __init__(self):
+        self.hand = []
+
+    def generate(self, n: int) -> 'Hand':
+        self.hand = [x for x in range(n)]
+        return self
+
+    def deal_into_new_stack(self) -> 'Hand':
+        self.hand = list(reversed(self.hand))
+        return self
+
+    def cut(self, n: int) -> 'Hand':
+        if n >= 0:
+            cache = self.hand[:n]
+            self.hand = self.hand[n:]
+            self.hand += cache
+        else:
+            cache = self.hand[n:]
+            self.hand = self.hand[:n]
+            self.hand = cache + self.hand
+        return self
+
+    def deal_with_increment(self, n: int) -> 'Hand':
+        cache = [0 for _ in range(len(self.hand))]
+        ptr_o = -1
+        ptr_n = -n
+        while (ptr_o := ptr_o + 1) < len(self.hand):
+            cache[(ptr_n := ptr_n + n) % len(cache)] = self.hand[ptr_o]
+        self.hand = cache
+        return self
+
+    def find_card(self, card: int) -> int:
+        for i in range(len(self.hand)):
+            if self.hand[i] == card:
+                return i
+        return -1
+
+    def find_position(self, position: int) -> int:
+        return self.hand[position]
+
+    def __str__(self):
+        return str(self.hand)
+
+
+def solve_p1(tape: list[Tuple[Command, int]], cards: int) -> int:
+    my_hand = Hand()
+    my_hand.generate(cards)
+    for command, param in tape:
+        if command == Command.CUT:
+            my_hand.cut(param)
+        elif command == Command.INC:
+            my_hand.deal_with_increment(param)
+        elif command == Command.STA:
+            my_hand.deal_into_new_stack()
+    return my_hand.find_card(2019)
+
+
+TAPE = parse_data()
+print(solve_p1(TAPE, 10007))
+
+
+def solve_p2(tape: list[Tuple[Command, int]], cards: int, repeats: int) -> int:
+    my_hand = Hand()
+    my_hand.generate(cards)
+    for _ in range(repeats):
+        for command, param in tape:
+            if command == Command.CUT:
+                my_hand.cut(param)
+            elif command == Command.INC:
+                my_hand.deal_with_increment(param)
+            elif command == Command.STA:
+                my_hand.deal_into_new_stack()
+    return my_hand.find_position(2020)
+
+
+# Takes way too long, need better solution
+print(solve_p2(TAPE, 119315717514047, 101741582076661))