Create day24.py

2020/Python/day24.py

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+from enum import Enum
+from typing import Tuple
+
+
+class Direction(Enum):
+    E = 0
+    SE = 1
+    SW = 2
+    W = 3
+    NW = 4
+    NE = 5
+
+
+def convert_string(path: str) -> list[Direction]:
+    out, i = [], 0
+    while i < len(path):
+        char = path[i]
+        if char in ['s', 'n']:
+            i += 1
+            char += path[i]
+        if char == "e":
+            out.append(Direction.E)
+        elif char == "w":
+            out.append(Direction.W)
+        elif char == "ne":
+            out.append(Direction.NE)
+        elif char == "nw":
+            out.append(Direction.NW)
+        elif char == "se":
+            out.append(Direction.SE)
+        elif char == "sw":
+            out.append(Direction.SW)
+        i += 1
+    return out
+
+
+def determine_neighbour(row: int, col: int, direction: Direction) -> Tuple[int, int]:
+    if direction == Direction.E:
+        return row, col+1
+    elif direction == Direction.SE:
+        return (row+1, col+1) if row % 2 == 0 else (row+1, col)
+    elif direction == Direction.SW:
+        return (row+1, col) if row % 2 == 0 else (row+1, col-1)
+    elif direction == Direction.W:
+        return row, col-1
+    elif direction == Direction.NW:
+        return (row-1, col) if row % 2 == 0 else (row-1, col-1)
+    elif direction == Direction.NE:
+        return (row-1, col+1) if row % 2 == 0 else (row-1, col)
+
+
+def find_tile(start_r: int, start_c: int, path: str) -> Tuple[int, int]:
+    path = convert_string(path)
+    tile_r, tile_c = start_r, start_c
+    for direction in path:
+        tile_r, tile_c = determine_neighbour(tile_r, tile_c, direction)
+    return tile_r, tile_c
+
+
+def parse_data() -> list[str]:
+    out = []
+    with open("input.txt") as file:
+        for line in file:
+            out.append(line.rstrip())
+    return out
+
+
+def solve_p1(data: list[str]) -> int:
+    black_tiles: set[Tuple[int, int]] = set()
+    for line in data:
+        found_tile = find_tile(0, 0, line)
+        if found_tile in black_tiles:
+            black_tiles.remove(found_tile)
+        else:
+            black_tiles.add(found_tile)
+    return len(black_tiles)
+
+
+DATA = parse_data()
+print(solve_p1(DATA))