kosom oop

#include <iostream>
using namespace std;

class vehicle
{
protected:
    int manufacturerID, noCylinders;
public:
    vehicle(int mID, int nCyl)
    {
        manufacturerID = mID;
        noCylinders = nCyl;
    }
    void set_mID (int mID)
    {
        manufacturerID = mID;
    }
    void set_nCyl (int nCyl)
    {
        noCylinders = nCyl;
    }
    int get_mID ()
    {
        return manufacturerID;
    }
    int get_nCyl ()
    {
        return noCylinders;
    }
};

class truck: public vehicle
{
    double loadCapacity, towingCapacity;
public:
    truck(int mID, int nCyl, double lCap, double tCap)
    {
        set_mID(mID);
        set_nCyl(nCyl);
        loadCapacity = lCap;
        towingCapacity = tCap;
    }
    void set_lCap(double lCap)
    {
        loadCapacity = lCap;
    }
    void set_tCap(double tCap)
    {
        towingCapacity = tCap;
    }
    double get_lCap()
    {
        return loadCapacity;
    }
    double get_tCap()
    {
        return towingCapacity;
    }
};

int main()
{
    vehicle vehicle1(9, 3);
    cout << "Vehicle 1's Manufacturer ID: " << vehicle1.get_mID() << "\tVehicle 1's Number of Cylinders: " << vehicle1.get_nCyl() << endl;
    vehicle1.set_mID(5);
    vehicle1.set_nCyl(8);
    cout << "Vehicle 1's Manufacturer ID: " << vehicle1.get_mID() << "\tVehicle 1's Number of Cylinders: " << vehicle1.get_nCyl() << endl;
    truck truck1(1, 8, 9.4, 5.5);
    cout << "Truck 1's Manufacturer ID: " << truck1.get_mID() << "\tVehicle 1's Number of Cylinders: " << truck1.get_nCyl() << endl;
    cout << "Truck 1's Load Capacity: " << truck1.get_lCap() << "\tTruck 1's Towing Capacity: " << truck1.get_tCap() << endl;
    truck1.set_mID(6);
    truck1.set_nCyl(8);
    truck1.set_lCap(1.2);
    truck1.set_tCap(7.9);
    cout << "Truck 1's Manufacturer ID: " << truck1.get_mID() << "\tVehicle 1's Number of Cylinders: " << truck1.get_nCyl() << endl;
    cout << "Truck 1's Load Capacity: " << truck1.get_lCap() << "\tTruck 1's Towing Capacity: " << truck1.get_tCap() << endl;
}