algoadvance

Leetcode 1603. Design Parking System

Problem Statement

Leetcode Problem 1603 - Design Parking System

You are required to design a parking system for a parking lot. The parking lot has different slots for different sizes of cars:

• big: cars that take big slots.
• medium: cars that take medium slots.
• small: cars that take small slots.

At the start, the parking lot contains a certain number of slots for each size. You need to provide functionality to add a car of different sizes into the parking lot. If there is still a place in the slot for the car size, it is parked successfully and true is returned. Otherwise, false is returned.

Implement the ParkingSystem class:

• ParkingSystem(int big, int medium, int small) - initializes the object with big, medium, and small slots.
• bool addCar(int carType) - checks whether there is some space available for the car type carType. carType can be one of three types:
  • 1: represents a big car
  • 2: represents a medium car
  • 3: represents a small car

Clarifying Questions

1. Initial Slots: Can the initial number of slots for each type be zero?
2. Concurrent Access: Can we assume there is no concurrent access (single-threaded execution)?
3. Valid Input: Can we assume the input is always valid, meaning carType will always be in the set {1, 2, 3}?

Code

#include <iostream>

class ParkingSystem {
private:
    int big;
    int medium;
    int small;

public:
    ParkingSystem(int big, int medium, int small) : big(big), medium(medium), small(small) {}

    bool addCar(int carType) {
        if (carType == 1) {
            if (big > 0) {
                big--;
                return true;
            }
        } else if (carType == 2) {
            if (medium > 0) {
                medium--;
                return true;
            }
        } else if (carType == 3) {
            if (small > 0) {
                small--;
                return true;
            }
        }
        return false;
    }
};

// Example of usage
int main() {
    ParkingSystem* parkingSystem = new ParkingSystem(1, 1, 0);
    std::cout << parkingSystem->addCar(1) << std::endl; // returns true because there is 1 available slot for a big car
    std::cout << parkingSystem->addCar(2) << std::endl; // returns true because there is 1 available slot for a medium car
    std::cout << parkingSystem->addCar(3) << std::endl; // returns false because there is no available slot for a small car
    std::cout << parkingSystem->addCar(1) << std::endl; // returns false because there is no available slot for a big car, it is already occupied
    delete parkingSystem;
    return 0;
}

Strategy

• Initialize the parking slots for big, medium, and small cars as member variables.
• In the addCar function, check the carType:
  • If carType is 1, decrement the big slot count if it’s greater than 0 and return true.
  • If carType is 2, decrement the medium slot count if it’s greater than 0 and return true.
  • If carType is 3, decrement the small slot count if it’s greater than 0 and return true.
  • If no slot is available for the specified type, return false.

Time Complexity

• The time complexity of the addCar function is O(1), as it involves a few constant-time checks and comparisons.
• The space complexity of the ParkingSystem class is O(1), as it uses a fixed amount of space to store the slot counts for each car type.

The solution provided is efficient and meets the problem requirements effectively.

Cut your prep time in half and DOMINATE your interview with AlgoAdvance AI

• Got blindsided by a question you didn’t expect?

• Spend too much time studying?

• Or simply don’t have the time to go over all 3000 questions?