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Java

Need help with multi-threading assignment (Buyer/Seller) in java eclipse

I must implement my run methods for buyer and seller in such a way that the buyer doesn't immediately buy from carshowroom list after appearing and seller doesn't immediately sell a car after showing up on list.

Below is my code and the output for it

package Assignment2Multithreading;

import java.util.Random;

public class Main {

public static void main(String args[]) throws InterruptedException {

    CarShowroom c = new CarShowroom();

    for(int i = 1; i<=30; i++) {

        Seller s = new Seller(c);

        Buyer b = new Buyer(c);

        if(c.numCarsInShowroom() == 1) {
            System.out.println("\nDay " + String.valueOf(i) + " There is one car in the show room today.\n");



        }
        else {
            System.out.println("\nDay " + String.valueOf(i) + " There are " + c.numCarsInShowroom() + " cars in the show room today.\n");

        }

        s.init();

        b.init();

        Thread.sleep(1000);


    }


}

}

package Assignment2Multithreading;

import java.util.ArrayList; import java.util.Random; import java.util.concurrent.atomic.AtomicInteger;

public class CarShowroom {

public static final int fullCapacity = 10;

private ArrayList<Car> carList= new ArrayList<Car>();

AtomicInteger saleNumber = new AtomicInteger();


public CarShowroom() {

}

public boolean isEmpty() {

    if(this.carList.isEmpty()) {

        return true;


    }
    return false;
}

public boolean isFull() {

    if(carList.size() == fullCapacity) {

        return true;
    }

    return false;
}

public synchronized void addCar(Car c) {


    carList.add(c);


}


public synchronized Car takeCar() {

    Car car = carList.remove(0);


    return car;
}




public int numCarsInShowroom() {

    return carList.size();
}

}

package Assignment2Multithreading;

import java.util.Random; import java.util.concurrent.atomic.AtomicInteger;

public class Seller implements Runnable{

CarShowroom carshowroom;

public Car car;

Random rand = new Random();

int numSale;

private static AtomicInteger sellerID  = new AtomicInteger(0);

private static AtomicInteger saleNumber = new AtomicInteger(0);

//private static long sellerID = 0;

/*public static synchronized String createSellerID()
{
    return String.valueOf(++sellerID);
} */


public Seller() {


    this.carshowroom = new CarShowroom();
    this.car = new Car();

}



public Seller(CarShowroom c) {


    this.carshowroom = c;
    this.car = new Car();
}

public void init() {

    Thread t;

    int n = rand.nextInt(3)+ 1;

    for(int i =0 ; i< n; i++) {

        t = new Thread(this);
        t.start();
    }

}






public void run() {




    synchronized(carshowroom) {


        try {

            sellerID.getAndIncrement();

            System.out.println("A new seller # " + sellerID + " just appeared with " + car + " to sell.");



            while(carshowroom.isFull()) {

                System.out.println("Seller # "+ sellerID + " is trying to sell a car but the showroom is full.");

                carshowroom.wait();
            }

            Thread.sleep(20);

            carshowroom.addCar(car);

            saleNumber.getAndIncrement();

            System.out.println("Seller # "+ sellerID + " sold "+ car);

            System.out.println("This is sale number " + saleNumber);

            //wait(1000);

            carshowroom.notifyAll();




        }catch(Exception e) {

            e.printStackTrace();
        }
    }


}

}

package Assignment2Multithreading;

import java.util.Random; import java.util.UUID; import java.util.concurrent.atomic.AtomicInteger;

public class Buyer implements Runnable{

CarShowroom carshowroom;

private static AtomicInteger newPurchase  = new AtomicInteger(0);

private static AtomicInteger buyerID = new AtomicInteger(0);

Random rand = new Random();

Car car;


public Buyer() {

    this.carshowroom = new CarShowroom();



}

public Buyer(CarShowroom c) {

    this.carshowroom = c;
}

public void init() { // we create the threads from within a method in the task class (that's fine)
    Thread t;


    int n = rand.nextInt(3) + 1;


    for(int j=0 ; j< n; j++) {



        t = new Thread(this); 
        t.start();




    }
}




public void run() {



    synchronized(carshowroom){

        try {


            buyerID.getAndIncrement();

            System.out.println("A new buyer # " + buyerID + " has appeared");




            while(carshowroom.isEmpty()) {

                System.out.println("Buyer # " + buyerID + " is trying to buy a car but the showroom is empty.");

                carshowroom.wait();

            }

            Thread.sleep(20);

            Car car = carshowroom.takeCar();




            newPurchase.getAndIncrement();

            System.out.println("Buyer # " + buyerID + " bought " + car);

            System.out.println("This is purchase number " + newPurchase);


            carshowroom.notifyAll();





        }catch(Exception e) {
            e.printStackTrace();
        }

    }


}

}

Day 1 There are 0 cars in the show room today.

A new seller # 1 just appeared with yellow car with registration 39-KY-8621 worth €16299 to sell. Seller # 1 sold yellow car with registration 39-KY-8621 worth €16299 This is sale number 1 A new buyer # 1 has appeared Buyer # 1 bought yellow car with registration 39-KY-8621 worth €16299 This is purchase number 1 A new buyer # 2 has appeared Buyer # 2 is trying to buy a car but the showroom is empty. A new seller # 2 just appeared with yellow car with registration 39-KY-8621 worth €16299 to sell. Seller # 2 sold yellow car with registration 39-KY-8621 worth €16299 This is sale number 2 Buyer # 2 bought yellow car with registration 39-KY-8621 worth €16299 This is purchase number 2

Day 2 There are 0 cars in the show room today.

A new seller # 3 just appeared with black car with registration 83-CE-1538 worth €13490 to sell. Seller # 3 sold black car with registration 83-CE-1538 worth €13490 This is sale number 3 A new buyer # 3 has appeared Buyer # 3 bought black car with registration 83-CE-1538 worth €13490 This is purchase number 3

Day 3 There are 0 cars in the show room today.

A new seller # 4 just appeared with yellow car with registration 84-LH-318 worth €3570 to sell. Seller # 4 sold yellow car with registration 84-LH-318 worth €3570 This is sale number 4 A new buyer # 4 has appeared Buyer # 4 bought yellow car with registration 84-LH-318 worth €3570 This is purchase number 4 A new buyer # 5 has appeared Buyer # 5 is trying to buy a car but the showroom is empty. A new seller # 5 just appeared with yellow car with registration 84-LH-318 worth €3570 to sell. Seller # 5 sold yellow car with registration 84-LH-318 worth €3570 This is sale number 5 A new seller # 6 just appeared with yellow car with registration 84-LH-318 worth €3570 to sell. Seller # 6 sold yellow car with registration 84-LH-318 worth €3570 This is sale number 6 Buyer # 5 bought yellow car with registration 84-LH-318 worth €3570 This is purchase number 5

Day 4 There is one car in the show room today.

A new seller # 7 just appeared with black car with registration 72-T-5799 worth €613 to sell. Seller # 7 sold black car with registration 72-T-5799 worth €613 This is sale number 7 A new buyer # 6 has appeared Buyer # 6 bought yellow car with registration 84-LH-318 worth €3570 This is purchase number 6 A new buyer # 7 has appeared Buyer # 7 bought black car with registration 72-T-5799 worth €613 This is purchase number 7

Day 5 There are 0 cars in the show room today.

A new seller # 8 just appeared with black car with registration 47-OY-5300 worth €9291 to sell. Seller # 8 sold black car with registration 47-OY-5300 worth €9291 This is sale number 8 A new buyer # 8 has appeared Buyer # 8 bought black car with registration 47-OY-5300 worth €9291 This is purchase number 8 A new buyer # 9 has appeared Buyer # 9 is trying to buy a car but the showroom is empty. A new buyer # 10 has appeared Buyer # 10 is trying to buy a car but the showroom is empty. A new seller # 9 just appeared with black car with registration 47-OY-5300 worth €9291 to sell. Seller # 9 sold black car with registration 47-OY-5300 worth €9291 This is sale number 9 Buyer # 10 bought black car with registration 47-OY-5300 worth €9291 This is purchase number 9 Buyer # 10 is trying to buy a car but the showroom is empty.

Day 6 There are 0 cars in the show room today.

A new seller # 10 just appeared with blue car with registration 67-WH-9581 worth €4976 to sell. Seller # 10 sold blue car with registration 67-WH-9581 worth €4976 This is sale number 10 Buyer # 10 bought blue car with registration 67-WH-9581 worth €4976 This is purchase number 10 A new buyer # 11 has appeared Buyer # 11 is trying to buy a car but the showroom is empty. A new buyer # 12 has appeared Buyer # 12 is trying to buy a car but the showroom is empty.

Day 7 There are 0 cars in the show room today.

A new seller # 11 just appeared with black car with registration 5-WH-1705 worth €9466 to sell. Seller # 11 sold black car with registration 5-WH-1705 worth €9466 This is sale number 11 Buyer # 12 bought black car with registration 5-WH-1705 worth €9466 This is purchase number 11 Buyer # 12 is trying to buy a car but the showroom is empty. A new buyer # 13 has appeared Buyer # 13 is trying to buy a car but the showroom is empty. A new buyer # 14 has appeared Buyer # 14 is trying to buy a car but the showroom is empty. A new seller # 12 just appeared with black car with registration 5-WH-1705 worth €9466 to sell. Seller # 12 sold black car with registration 5-WH-1705 worth €9466 This is sale number 12 A new seller # 13 just appeared with black car with registration 5-WH-1705 worth €9466 to sell. Seller # 13 sold black car with registration 5-WH-1705 worth €9466 This is sale number 13 Buyer # 14 bought black car with registration 5-WH-1705 worth €9466 This is purchase number 12 Buyer # 14 bought black car with registration 5-WH-1705 worth €9466 This is purchase number 13 Buyer # 14 is trying to buy a car but the showroom is empty.

Day 8 There are 0 cars in the show room today.

A new seller # 14 just appeared with red car with registration 60-LH-2011 worth €12711 to sell. Seller # 14 sold red car with registration 60-LH-2011 worth €12711 This is sale number 14 Buyer # 14 bought red car with registration 60-LH-2011 worth €12711 This is purchase number 14 A new buyer # 15 has appeared Buyer # 15 is trying to buy a car but the showroom is empty. A new buyer # 16 has appeared Buyer # 16 is trying to buy a car but the showroom is empty. A new seller # 15 just appeared with red car with registration 60-LH-2011 worth €12711 to sell. Seller # 15 sold red car with registration 60-LH-2011 worth €12711 This is sale number 15 A new seller # 16 just appeared with red car with registration 60-LH-2011 worth €12711 to sell. Seller # 16 sold red car with registration 60-LH-2011 worth €12711 This is sale number 16 Buyer # 16 bought red car with registration 60-LH-2011 worth €12711 This is purchase number 15 Buyer # 16 bought red car with registration 60-LH-2011 worth €12711 This is purchase number 16

Day 9 There are 0 cars in the show room today.

A new seller # 17 just appeared with blue car with registration 91-LS-9839 worth €5057 to sell. Seller # 17 sold blue car with registration 91-LS-9839 worth €5057 This is sale number 17 A new buyer # 17 has appeared Buyer # 17 bought blue car with registration 91-LS-9839 worth €5057 This is purchase number 17 A new seller # 18 just appeared with blue car with registration 91-LS-9839 worth €5057 to sell. Seller # 18 sold blue car with registration 91-LS-9839 worth €5057 This is sale number 18

Day 10 There is one car in the show room today.

A new seller # 19 just appeared with green car with registration 51-OY-7800 worth €17830 to sell. Seller # 19 sold green car with registration 51-OY-7800 worth €17830 This is sale number 19 A new buyer # 18 has appeared Buyer # 18 bought blue car with registration 91-LS-9839 worth €5057 This is purchase number 18

Day 11 There is one car in the show room today.

A new seller # 20 just appeared with blue car with registration 52-WH-5776 worth €4073 to sell. Seller # 20 sold blue car with registration 52-WH-5776 worth €4073 This is sale number 20 A new buyer # 19 has appeared Buyer # 19 bought green car with registration 51-OY-7800 worth €17830 This is purchase number 19 A new buyer # 20 has appeared Buyer # 20 bought blue car with registration 52-WH-5776 worth €4073 This is purchase number 20 A new buyer # 21 has appeared Buyer # 21 is trying to buy a car but the showroom is empty. A new seller # 21 just appeared with blue car with registration 52-WH-5776 worth €4073 to sell. Seller # 21 sold blue car with registration 52-WH-5776 worth €4073 This is sale number 21 Buyer # 21 bought blue car with registration 52-WH-5776 worth €4073 This is purchase number 21

Day 12 There are 0 cars in the show room today.

A new seller # 22 just appeared with black car with registration 73-W-216 worth €3267 to sell. Seller # 22 sold black car with registration 73-W-216 worth €3267 This is sale number 22 A new buyer # 22 has appeared Buyer # 22 bought black car with registration 73-W-216 worth €3267 This is purchase number 22

Day 13 There are 0 cars in the show room today.

A new seller # 23 just appeared with silver car with registration 97-KY-673 worth €151 to sell. Seller # 23 sold silver car with registration 97-KY-673 worth €151 This is sale number 23 A new buyer # 23 has appeared Buyer # 23 bought silver car with registration 97-KY-673 worth €151 This is purchase number 23 A new buyer # 24 has appeared Buyer # 24 is trying to buy a car but the showroom is empty.

Day 14 There are 0 cars in the show room today.

A new seller # 24 just appeared with green car with registration 46-KK-4063 worth €5568 to sell. Seller # 24 sold green car with registration 46-KK-4063 worth €5568 This is sale number 24 Buyer # 24 bought green car with registration 46-KK-4063 worth €5568 This is purchase number 24 A new buyer # 25 has appeared Buyer # 25 is trying to buy a car but the showroom is empty. A new buyer # 26 has appeared Buyer # 26 is trying to buy a car but the showroom is empty. A new buyer # 27 has appeared Buyer # 27 is trying to buy a car but the showroom is empty. A new seller # 25 just appeared with green car with registration 46-KK-4063 worth €5568 to sell. Seller # 25 sold green car with registration 46-KK-4063 worth €5568 This is sale number 25 A new seller # 26 just appeared with green car with registration 46-KK-4063 worth €5568 to sell. Seller # 26 sold green car with registration 46-KK-4063 worth €5568 This is sale number 26 Buyer # 27 bought green car with registration 46-KK-4063 worth €5568 This is purchase number 25 Buyer # 27 bought green car with registration 46-KK-4063 worth €5568 This is purchase number 26 Buyer # 27 is trying to buy a car but the showroom is empty.

Day 15 There are 0 cars in the show room today.

A new seller # 27 just appeared with silver car with registration 17-LH-6046 worth €12063 to sell. Seller # 27 sold silver car with registration 17-LH-6046 worth €12063 This is sale number 27 Buyer # 27 bought silver car with registration 17-LH-6046 worth €12063 This is purchase number 27 A new buyer # 28 has appeared Buyer # 28 is trying to buy a car but the showroom is empty. A new buyer # 29 has appeared Buyer # 29 is trying to buy a car but the showroom is empty. A new buyer # 30 has appeared Buyer # 30 is trying to buy a car but the showroom is empty. A new seller # 28 just appeared with silver car with registration 17-LH-6046 worth €12063 to sell. Seller # 28 sold silver car with registration 17-LH-6046 worth €12063 This is sale number 28 A new seller # 29 just appeared with silver car with registration 17-LH-6046 worth €12063 to sell. Seller # 29 sold silver car with registration 17-LH-6046 worth €12063 This is sale number 29 Buyer # 30 bought silver car with registration 17-LH-6046 worth €12063 This is purchase number 28 Buyer # 30 bought silver car with registration 17-LH-6046 worth €12063 This is purchase number 29 Buyer # 30 is trying to buy a car but the showroom is empty.

Day 16 There are 0 cars in the show room today.

A new seller # 30 just appeared with yellow car with registration 61-W-7827 worth €2743 to sell. Seller # 30 sold yellow car with registration 61-W-7827 worth €2743 This is sale number 30 Buyer # 30 bought yellow car with registration 61-W-7827 worth €2743 This is purchase number 30 A new buyer # 31 has appeared Buyer # 31 is trying to buy a car but the showroom is empty. A new buyer # 32 has appeared Buyer # 32 is trying to buy a car but the showroom is empty. A new buyer # 33 has appeared Buyer # 33 is trying to buy a car but the showroom is empty.

Day 17 There are 0 cars in the show room today.

A new seller # 31 just appeared with green car with registration 67-MH-4999 worth €2728 to sell. Seller # 31 sold green car with registration 67-MH-4999 worth €2728 This is sale number 31 Buyer # 33 bought green car with registration 67-MH-4999 worth €2728 This is purchase number 31 Buyer # 33 is trying to buy a car but the showroom is empty. Buyer # 33 is trying to buy a car but the showroom is empty. A new buyer # 34 has appeared Buyer # 34 is trying to buy a car but the showroom is empty. A new seller # 32 just appeared with green car with registration 67-MH-4999 worth €2728 to sell. Seller # 32 sold green car with registration 67-MH-4999 worth €2728 This is sale number 32 Buyer # 34 bought green car with registration 67-MH-4999 worth €2728 This is purchase number 32 Buyer # 34 is trying to buy a car but the showroom is empty. Buyer # 34 is trying to buy a car but the showroom is empty.

Day 18 There are 0 cars in the show room today.

A new seller # 33 just appeared with black car with registration 61-C-8774 worth €10371 to sell. Seller # 33 sold black car with registration 61-C-8774 worth €10371 This is sale number 33 Buyer # 34 bought black car with registration 61-C-8774 worth €10371 This is purchase number 33 Buyer # 34 is trying to buy a car but the showroom is empty. A new buyer # 35 has appeared Buyer # 35 is trying to buy a car but the showroom is empty. A new seller # 34 just appeared with black car with registration 61-C-8774 worth €10371 to sell. Seller # 34 sold black car with registration 61-C-8774 worth €10371 This is sale number 34 A new seller # 35 just appeared with black car with registration 61-C-8774 worth €10371 to sell. Seller # 35 sold black car with registration 61-C-8774 worth €10371 This is sale number 35 Buyer # 35 bought black car with registration 61-C-8774 worth €10371 This is purchase number 34 Buyer # 35 bought black car with registration 61-C-8774 worth €10371 This is purchase number 35

Day 19 There are 0 cars in the show room today.

A new seller # 36 just appeared with blue car with registration 94-CW-4050 worth €17974 to sell. Seller # 36 sold blue car with registration 94-CW-4050 worth €17974 This is sale number 36 A new buyer # 36 has appeared Buyer # 36 bought blue car with registration 94-CW-4050 worth €17974 This is purchase number 36 A new seller # 37 just appeared with blue car with registration 94-CW-4050 worth €17974 to sell. Seller # 37 sold blue car with registration 94-CW-4050 worth €17974 This is sale number 37 A new seller # 38 just appeared with blue car with registration 94-CW-4050 worth €17974 to sell. Seller # 38 sold blue car with registration 94-CW-4050 worth €17974 This is sale number 38

Day 20 There are 2 cars in the show room today.

A new seller # 39 just appeared with black car with registration 97-DL-8187 worth €14071 to sell. Seller # 39 sold black car with registration 97-DL-8187 worth €14071 This is sale number 39 A new buyer # 37 has appeared Buyer # 37 bought blue car with registration 94-CW-4050 worth €17974 This is purchase number 37 A new buyer # 38 has appeared Buyer # 38 bought blue car with registration 94-CW-4050 worth €17974 This is purchase number 38 A new seller # 40 just appeared with black car with registration 97-DL-8187 worth €14071 to sell. Seller # 40 sold black car with registration 97-DL-8187 worth €14071 This is sale number 40 A new seller # 41 just appeared with black car with registration 97-DL-8187 worth €14071 to sell. Seller # 41 sold black car with registration 97-DL-8187 worth €14071 This is sale number 41

Day 21 There are 3 cars in the show room today.

A new seller # 42 just appeared with green car with registration 72-WX-7080 worth €2507 to sell. Seller # 42 sold green car with registration 72-WX-7080 worth €2507 This is sale number 42 A new buyer # 39 has appeared Buyer # 39 bought black car with registration 97-DL-8187 worth €14071 This is purchase number 39 A new buyer # 40 has appeared Buyer # 40 bought black car with registration 97-DL-8187 worth €14071 This is purchase number 40 A new seller # 43 just appeared with green car with registration 72-WX-7080 worth €2507 to sell. Seller # 43 sold green car with registration 72-WX-7080 worth €2507 This is sale number 43 A new seller # 44 just appeared with green car with registration 72-WX-7080 worth €2507 to sell. Seller # 44 sold green car with registration 72-WX-7080 worth €2507 This is sale number 44

Day 22 There are 4 cars in the show room today.

A new seller # 45 just appeared with black car with registration 43-T-9191 worth €2317 to sell. Seller # 45 sold black car with registration 43-T-9191 worth €2317 This is sale number 45 A new buyer # 41 has appeared Buyer # 41 bought black car with registration 97-DL-8187 worth €14071 This is purchase number 41 A new buyer # 42 has appeared Buyer # 42 bought green car with registration 72-WX-7080 worth €2507 This is purchase number 42 A new buyer # 43 has appeared Buyer # 43 bought green car with registration 72-WX-7080 worth €2507 This is purchase number 43 A new seller # 46 just appeared with black car with registration 43-T-9191 worth €2317 to sell. Seller # 46 sold black car with registration 43-T-9191 worth €2317 This is sale number 46 A new seller # 47 just appeared with black car with registration 43-T-9191 worth €2317 to sell. Seller # 47 sold black car with registration 43-T-9191 worth €2317 This is sale number 47

Day 23 There are 4 cars in the show room today.

A new seller # 48 just appeared with black car with registration 92-KY-5722 worth €15709 to sell. Seller # 48 sold black car with registration 92-KY-5722 worth €15709 This is sale number 48 A new buyer # 44 has appeared Buyer # 44 bought green car with registration 72-WX-7080 worth €2507 This is purchase number 44 A new buyer # 45 has appeared Buyer # 45 bought black car with registration 43-T-9191 worth €2317 This is purchase number 45 A new buyer # 46 has appeared Buyer # 46 bought black car with registration 43-T-9191 worth €2317 This is purchase number 46 A new seller # 49 just appeared with black car with registration 92-KY-5722 worth €15709 to sell. Seller # 49 sold black car with registration 92-KY-5722 worth €15709 This is sale number 49

Day 24 There are 3 cars in the show room today.

A new seller # 50 just appeared with silver car with registration 49-T-5853 worth €4769 to sell. Seller # 50 sold silver car with registration 49-T-5853 worth €4769 This is sale number 50 A new buyer # 47 has appeared Buyer # 47 bought black car with registration 43-T-9191 worth €2317 This is purchase number 47 A new buyer # 48 has appeared Buyer # 48 bought black car with registration 92-KY-5722 worth €15709 This is purchase number 48 A new seller # 51 just appeared with silver car with registration 49-T-5853 worth €4769 to sell. Seller # 51 sold silver car with registration 49-T-5853 worth €4769 This is sale number 51 A new seller # 52 just appeared with silver car with registration 49-T-5853 worth €4769 to sell. Seller # 52 sold silver car with registration 49-T-5853 worth €4769 This is sale number 52

Day 25 There are 4 cars in the show room today.

A new seller # 53 just appeared with green car with registration 56-KY-4864 worth €5720 to sell. Seller # 53 sold green car with registration 56-KY-4864 worth €5720 This is sale number 53 A new buyer # 49 has appeared Buyer # 49 bought black car with registration 92-KY-5722 worth €15709 This is purchase number 49 A new buyer # 50 has appeared Buyer # 50 bought silver car with registration 49-T-5853 worth €4769 This is purchase number 50 A new buyer # 51 has appeared Buyer # 51 bought silver car with registration 49-T-5853 worth €4769 This is purchase number 51 A new seller # 54 just appeared with green car with registration 56-KY-4864 worth €5720 to sell. Seller # 54 sold green car with registration 56-KY-4864 worth €5720 This is sale number 54

Day 26 There are 3 cars in the show room today.

A new seller # 55 just appeared with red car with registration 11-C-7501 worth €9980 to sell. Seller # 55 sold red car with registration 11-C-7501 worth €9980 This is sale number 55 A new buyer # 52 has appeared Buyer # 52 bought silver car with registration 49-T-5853 worth €4769 This is purchase number 52 A new buyer # 53 has appeared Buyer # 53 bought green car with registration 56-KY-4864 worth €5720 This is purchase number 53 A new seller # 56 just appeared with red car with registration 11-C-7501 worth €9980 to sell. Seller # 56 sold red car with registration 11-C-7501 worth €9980 This is sale number 56 A new seller # 57 just appeared with red car with registration 11-C-7501 worth €9980 to sell. Seller # 57 sold red car with registration 11-C-7501 worth €9980 This is sale number 57

Day 27 There are 4 cars in the show room today.

A new seller # 58 just appeared with blue car with registration 75-WH-5889 worth €12907 to sell. Seller # 58 sold blue car with registration 75-WH-5889 worth €12907 This is sale number 58 A new buyer # 54 has appeared Buyer # 54 bought green car with registration 56-KY-4864 worth €5720 This is purchase number 54 A new seller # 59 just appeared with blue car with registration 75-WH-5889 worth €12907 to sell. Seller # 59 sold blue car with registration 75-WH-5889 worth €12907 This is sale number 59 A new seller # 60 just appeared with blue car with registration 75-WH-5889 worth €12907 to sell. Seller # 60 sold blue car with registration 75-WH-5889 worth €12907 This is sale number 60

Day 28 There are 6 cars in the show room today.

A new seller # 61 just appeared with blue car with registration 36-LD-7452 worth €17871 to sell. Seller # 61 sold blue car with registration 36-LD-7452 worth €17871 This is sale number 61 A new buyer # 55 has appeared Buyer # 55 bought red car with registration 11-C-7501 worth €9980 This is purchase number 55 A new buyer # 56 has appeared Buyer # 56 bought red car with registration 11-C-7501 worth €9980 This is purchase number 56 A new buyer # 57 has appeared Buyer # 57 bought red car with registration 11-C-7501 worth €9980 This is purchase number 57 A new seller # 62 just appeared with blue car with registration 36-LD-7452 worth €17871 to sell. Seller # 62 sold blue car with registration 36-LD-7452 worth €17871 This is sale number 62 A new seller # 63 just appeared with blue car with registration 36-LD-7452 worth €17871 to sell. Seller # 63 sold blue car with registration 36-LD-7452 worth €17871 This is sale number 63

Day 29 There are 6 cars in the show room today.

A new seller # 64 just appeared with green car with registration 81-L-1413 worth €11149 to sell. Seller # 64 sold green car with registration 81-L-1413 worth €11149 This is sale number 64 A new buyer # 58 has appeared Buyer # 58 bought blue car with registration 75-WH-5889 worth €12907 This is purchase number 58 A new seller # 65 just appeared with green car with registration 81-L-1413 worth €11149 to sell. Seller # 65 sold green car with registration 81-L-1413 worth €11149 This is sale number 65

Day 30 There are 7 cars in the show room today.

A new seller # 66 just appeared with black car with registration 50-LH-997 worth €13133 to sell. Seller # 66 sold black car with registration 50-LH-997 worth €13133 This is sale number 66 A new buyer # 59 has appeared Buyer # 59 bought blue car with registration 75-WH-5889 worth €12907 This is purchase number 59 A new buyer # 60 has appeared Buyer # 60 bought blue car with registration 75-WH-5889 worth €12907 This is purchase number 60 A new seller # 67 just appeared with black car with registration 50-LH-997 worth €13133 to sell. Seller # 67 sold black car with registration 50-LH-997 worth €13133 This is sale number 67 A new seller # 68 just appeared with black car with registration 50-LH-997 worth €13133 to sell. Seller # 68 sold black car with registration 50-LH-997 worth €13133 This is sale number 68

This is the desired output:

Day 1 beginning. There are 0 cars in the showroom today. A new buyer #1 just appeared. Buyer #1 wants to buy a car, but the showroom is empty. A new seller #1 just appeared with a yellow car with registration 11-G-7212 worth €3944 to sell. A new seller #3 just appeared with a black car with registration 18-G-2743 worth €14040 to sell. Seller #1 sold their yellow car with registration 11-G-7212 worth €3944 to the showroom. This is sale number 1. A new seller #2 just appeared with a silver car with registration 18-G-2469 worth €1449 to sell. Buyer #1 bought a yellow car with registration 11-G-7212 worth €3944 from the showroom. This is purchase number 1. Seller #3 sold their black car with registration 18-G-2743 worth €14040 to the showroom. This is sale number 2. Seller #2 sold their silver car with registration 18-G-2469 worth €1449 to the showroom. This is sale number 3. Day 2 beginning. There are 2 cars in the showroom today. A new seller #4 just appeared with a black car with registration 18-G-5011 worth €10859 to sell.