Python3 || concise solution
```\nclass ParkingSystem:\n\n    def init(self, big: int, medium: int, small: int):\n        self.lot = []\n        self.lot.append(big)\n        self.lot.appen
```\nclass ParkingSystem:\n\n    def __init__(self, big: int, medium: int, small: int):\n        self.lot = []\n        self.lot.append(big)\n        self.lot.append(medium)\n        self.lot.append(small)\n\n    def addCar(self, carType: int) -> bool:\n        index = carType - 1\n        if self.lot[index] > 0:\n            self.lot[index] -= 1\n            return True\n        return False\n\t\t
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