| 1 | import random |
| 2 | import string |
| 3 | |
| 1 | 4 | class Robot: |
| 5 | """ |
| 6 | A class representing a robot with a randomly generated name. |
| 7 | |
| 8 | The robot's name consists of two uppercase letters followed by three digits. |
| 9 | Names are unique across all robot instances. |
| 10 | """ |
| 11 | |
| 12 | # Class-level set to store all generated names for uniqueness |
| 13 | _used_names = set() |
| 14 | |
| 2 | 15 | def __init__(self): |
| 3 | | pass |
| 4 | | |
| 16 | """ |
| 17 | Initialize a new Robot instance with no name. |
| 18 | The name will be generated on first access. |
| 19 | """ |
| 20 | self._name = None |
| 21 | |
| 5 | 22 | @property |
| 6 | 23 | def name(self) -> str: |
| 7 | | pass |
| 8 | | |
| 24 | """ |
| 25 | Get the robot's name. If the robot doesn't have a name yet, |
| 26 | generate a new unique random name. |
| 27 | |
| 28 | Returns: |
| 29 | str: The robot's name in format like 'AB123' |
| 30 | """ |
| 31 | # Edge Case: Robot has no name yet, generate one |
| 32 | if self._name is None: |
| 33 | self._generate_unique_name() |
| 34 | return self._name |
| 35 | |
| 9 | 36 | def reset(self) -> None: |
| 10 | | pass |
| 37 | """ |
| 38 | Reset the robot to factory settings by wiping its name. |
| 39 | The next access to the name property will generate a new unique name. |
| 40 | """ |
| 41 | # Edge Case: Resetting a robot that never had a name assigned |
| 42 | if self._name is not None: |
| 43 | # Remove the old name from the registry |
| 44 | Robot._used_names.discard(self._name) |
| 45 | # Clear the name so a new one will be generated on next access |
| 46 | self._name = None |
| 47 | |
| 48 | def _generate_unique_name(self) -> None: |
| 49 | """ |
| 50 | Generate a unique random name for the robot. |
| 51 | |
| 52 | The name format is two uppercase letters followed by three digits. |
| 53 | This method ensures the generated name is unique by checking against |
| 54 | a central registry of all used names. |
| 55 | """ |
| 56 | # Edge Case: All possible names are already used (theoretical limit) |
| 57 | # In practice, with 26*26*1000 = 676,000 possible names, this is extremely unlikely |
| 58 | while True: |
| 59 | # Generate two random uppercase letters |
| 60 | letters = ''.join(random.choices(string.ascii_uppercase, k=2)) |
| 61 | # Generate three random digits |
| 62 | digits = ''.join(random.choices(string.digits, k=3)) |
| 63 | # Combine to form the name |
| 64 | new_name = letters + digits |
| 65 | |
| 66 | # Check if this name is already used |
| 67 | if new_name not in Robot._used_names: |
| 68 | # If not used, assign it and add to the registry |
| 69 | self._name = new_name |
| 70 | Robot._used_names.add(new_name) |
| 71 | break |
| 72 | |
| 73 | # Handled Edge Cases: Robot has no name yet, resetting a robot that never had a name assigned, all possible names are already used |