Design Parking System

Problem statement

Design a parking system for a parking lot. The parking lot has three kinds of parking spaces: big, medium, and small, with a fixed number of slots for each size.

Implement the ParkingSystem class:

• ParkingSystem(int big, int medium, int small) Initializes object of the ParkingSystem class. The number of slots for each parking space are given as part of the constructor.
• bool addCar(int carType) Checks whether there is a parking space of carType for the car that wants to get into the parking lot. carType can be of three kinds: big, medium, or small, which are represented by 1, 2, and 3 respectively. A car can only park in a parking space of its carType. If there is no space available, return false, else park the car in that size space and return true.

Example 1:

Input["ParkingSystem", "addCar", "addCar", "addCar", "addCar"][[1, 1, 0], [1], [2], [3], [1]]Output[null, true, true, false, false]ExplanationParkingSystem parkingSystem = new ParkingSystem(1, 1, 0);parkingSystem.addCar(1); // return true because there is 1 available slot for a big carparkingSystem.addCar(2); // return true because there is 1 available slot for a medium carparkingSystem.addCar(3); // return false because there is no available slot for a small carparkingSystem.addCar(1); // return false because there is no available slot for a big car. It is already occupied.

Constraints:

• 0 <= big, medium, small <= 1000
• carType is 1, 2, or 3
• At most 1000 calls will be made to addCar

My solution

/**
 * @param {number} big
 * @param {number} medium
 * @param {number} small
 */
var ParkingSystem = function(big, medium, small) {
    this.bigSize = [big, 0];
    this.mediumSize = [medium, 0];
    this.smallSize = [small, 0];
};

/** 
 * @param {number} carType
 * @return {boolean}
 */
ParkingSystem.prototype.addCar = function(carType) {
    let wasTheCarParked = false;
    switch(carType) {
        case 1:
            wasTheCarParked = checkIfCarCanPark(this.bigSize)
            break;
        case 2:
            wasTheCarParked = checkIfCarCanPark(this.mediumSize)
            break;
        case 3:
            wasTheCarParked = checkIfCarCanPark(this.smallSize)
            break;
        default:
            break;
    }
    
    return wasTheCarParked;
};

function checkIfCarCanPark(config) {
    if (config[1] < config[0]) {
        config[1]++
        return true;
    }
    return false
}

/** 
 * Your ParkingSystem object will be instantiated and called as such:
 * var obj = new ParkingSystem(big, medium, small)
 * var param_1 = obj.addCar(carType)
 */