1import dataclasses 

2 

3 

4@dataclasses.dataclass 

5class Rover: 

6 x: int 

7 y: int 

8 direction: str 

9 obstacles: list[list[int]] = dataclasses.field(default_factory=list) 

10 

11 valid_commands = ("F", "B", "R", "L") 

12 

13 direction_map = { 

14 "NORTH": (0, 1, "WEST", "EAST"), 

15 "EAST": (1, 0, "NORTH", "SOUTH"), 

16 "SOUTH": (0, -1, "EAST", "WEST"), 

17 "WEST": (-1, 0, "SOUTH", "NORTH"), 

18 } 

19 

20 def is_valid_command(self, command): 

21 for ch in command: 

22 if ch not in self.valid_commands: 

23 return False 

24 

25 return True 

26 

27 def is_obstacle(self, x: int, y: int): 

28 return [x, y] in self.obstacles 

29 

30 def move(self, command: str): 

31 if not self.is_valid_command(command): 

32 raise ValueError("invalid command. The rover does not move") 

33 

34 for ch in command: 

35 x, y, direction = self._compute_new_coordinates(ch) 

36 if obstacle := self.is_obstacle(x, y): 

37 return self.new_coordinates_output(obstacle) 

38 

39 self.apply_new_coordinates(x, y, direction) 

40 

41 return self.new_coordinates_output() 

42 

43 def new_coordinates_output(self, obstacle: bool = False): 

44 if obstacle: 

45 return self.x, self.y, self.direction, "STOPPED" 

46 return self.x, self.y, self.direction 

47 

48 def _compute_new_coordinates(self, command): 

49 x = self.x 

50 y = self.y 

51 direction = self.direction 

52 

53 if command == "B": 

54 x -= self.direction_map[self.direction][0] 

55 y -= self.direction_map[self.direction][1] 

56 if command == "F": 

57 x += self.direction_map[self.direction][0] 

58 y += self.direction_map[self.direction][1] 

59 if command == "R": 

60 direction = self.direction_map[self.direction][3] 

61 if command == "L": 

62 direction = self.direction_map[self.direction][2] 

63 

64 return x, y, direction 

65 

66 def apply_new_coordinates(self, x, y, direction): 

67 self.x = x 

68 self.y = y 

69 self.direction = direction