How to create default constructor for pointer

void initCar(Queue&, Queue&);
Queue *q1, *q2; // Global variable

int main() {
   initCar(*q1, *q2);
}

void initCar(Queue &q1, Queue &q2) {
   Car c1 = Car("SJS1006Z","Toyota", "Saloon car");
	Car c2 = Car("SFW6666E", "hyundai", "Taxi (Saloon)");
	Car c3 = Car("SCF1006G","Mercedes", "Large Van");
	Car c4 = Car("SBQ1006Z", "Puma", "Saloon Car");

	q1.enqueue(c1);
	q2.enqueue(c1);
	q2.enqueue(c3);
	q1.enqueue(c4);
	q1.enqueue(c1);
	q1.enqueue(c1);
	q1.enqueue(c1);
	q2.enqueue(c2);
	q2.enqueue(c2);
}

//Default constructor 
#include "Car.h"
#include <iostream>
#include <string>

using namespace std;

const int Q_MAX_SIZE = 20;
class Queue {
private:
	int size; // size of the queue
	Car carQueue[Q_MAX_SIZE];
	int front, rear;
public:
	Queue();
	~Queue();
};

Queue::Queue() { // default constructor
	size = 0;
	front = 0;
	rear = Q_MAX_SIZE -1;
}

// Constructor for pointer ???? 
Queue::Queue*() {
	size = 0;
	front = 0;
	rear = Q_MAX_SIZE -1;
}