Easy to read Javascript solution with class constructor
\nclass ParkingSystem {\n    constructor(big, medium, small) {\n        this.slots = {\n            1: big,\n            2: medium,\n            3: small\n     
```\nclass ParkingSystem {\n    constructor(big, medium, small) {\n        this.slots = {\n            1: big,\n            2: medium,\n            3: small\n        };\n    }\n    \n    addCar(carType) {\n        if(this.slots[carType] === 0) {\n            return false;\n        }\n        \n        this.slots[carType]--;\n        return true;\n    };\n};\n```
['JavaScript']