68 lines
2.4 KiB
Python
68 lines
2.4 KiB
Python
|
def get_input(sample = False):
|
||
|
|
with open("sample" if sample else "input") as f:
|
||
|
|
return [(line[:1], int(line[1:])) for line in f.readlines()]
|
||
|
|
|
||
|
|
def new_dir_after_rotate(cur_dir: str, L_or_R: str, amount: int):
|
||
|
|
orientations = ["N", "E", "S", "W"]
|
||
|
|
cur_dir_i = orientations.index(cur_dir)
|
||
|
|
return orientations[(cur_dir_i + (1 if L_or_R == "R" else -1) * amount // 90) % len(orientations)]
|
||
|
|
|
||
|
|
def new_waypoint_after_rotate(cur_wp: list, L_or_R: str, amount: int):
|
||
|
|
ret = [0, 0]
|
||
|
|
|
||
|
|
rot = amount // 90 % 4
|
||
|
|
if (rot, L_or_R) == (1, "L") or (rot, L_or_R) == (3, "R"):
|
||
|
|
ret[0] = -cur_wp[1]
|
||
|
|
ret[1] = cur_wp[0]
|
||
|
|
elif rot == 2:
|
||
|
|
ret[0] = -cur_wp[0]
|
||
|
|
ret[1] = -cur_wp[1]
|
||
|
|
elif (rot, L_or_R) == (3, "L") or (rot, L_or_R) == (1, "R"):
|
||
|
|
ret[0] = cur_wp[1]
|
||
|
|
ret[1] = -cur_wp[0]
|
||
|
|
|
||
|
|
return ret
|
||
|
|
|
||
|
|
def get_result(instructions: dict, part = 1):
|
||
|
|
position = [0, 0]
|
||
|
|
waypoint = [10, 1]
|
||
|
|
cur_dir = "E"
|
||
|
|
|
||
|
|
|
||
|
|
add_to_vertical = lambda dir, x: (1 if dir == "N" else -1) * x
|
||
|
|
add_to_horizontal = lambda dir, x: (1 if dir == "E" else -1) * x
|
||
|
|
|
||
|
|
for cmd, amount in instructions:
|
||
|
|
if part == 1:
|
||
|
|
if cmd == "F":
|
||
|
|
if cur_dir in ["N", "S"]:
|
||
|
|
position[1] += add_to_vertical(cur_dir, amount)
|
||
|
|
elif cur_dir in ["E", "W"]:
|
||
|
|
position[0] += add_to_horizontal(cur_dir, amount)
|
||
|
|
elif cmd in ["L", "R"]:
|
||
|
|
cur_dir = new_dir_after_rotate(cur_dir, cmd, amount)
|
||
|
|
elif cmd in ["N", "E", "S", "W"]:
|
||
|
|
if cmd in ["N", "S"]:
|
||
|
|
position[1] += add_to_vertical(cmd, amount)
|
||
|
|
elif cmd in ["E", "W"]:
|
||
|
|
position[0] += add_to_horizontal(cmd, amount)
|
||
|
|
else:
|
||
|
|
if cmd == "F":
|
||
|
|
position[0] += waypoint[0] * amount
|
||
|
|
position[1] += waypoint[1] * amount
|
||
|
|
elif cmd in ["L", "R"]:
|
||
|
|
waypoint = new_waypoint_after_rotate(waypoint, cmd, amount)
|
||
|
|
elif cmd in ["N", "E", "S", "W"]:
|
||
|
|
if cmd in ["N", "S"]:
|
||
|
|
waypoint[1] += add_to_vertical(cmd, amount)
|
||
|
|
elif cmd in ["E", "W"]:
|
||
|
|
waypoint[0] += add_to_horizontal(cmd, amount)
|
||
|
|
|
||
|
|
|
||
|
|
return sum(map(lambda x: abs(x), position))
|
||
|
|
|
||
|
|
if __name__ == "__main__":
|
||
|
|
print(get_result(get_input(), part = 2))
|
||
|
|
|
||
|
|
|