diff --git a/Restaurant/Address.java b/Restaurant/Address.java
new file mode 100644
index 0000000..f7185c6
--- /dev/null
+++ b/Restaurant/Address.java
@@ -0,0 +1,33 @@
+public class Address {
+    public double longitude;
+    public double latitude;
+    public String writtenAddress;
+
+    public Address(double latitude, double longitude, String writtenAddress){
+        this.latitude = latitude;
+        this.longitude = longitude;
+        this.writtenAddress = writtenAddress;
+    }
+
+    public double getLatitude() {
+        return latitude;
+    }
+    public double getLongitude() {
+        return longitude;
+    }
+    public String getWrittenAddress() {
+        return writtenAddress;
+    }
+    public double distanceFrom(Address otherAddress){
+        double la1 = this.latitude;
+        double lo1 = this.longitude;
+        double la2 = otherAddress.getLatitude();
+        double lo2 = otherAddress.getLongitude();
+        double distance;
+        double x;
+        x = Math.pow((la2 - la1), 2) + Math.pow((lo2 - lo1), 2);
+        distance = Math.pow(x, 0.5);
+
+        return Math.round(distance * 100000.0) / 100000.0;
+    }
+}
diff --git a/Restaurant/Customer.java b/Restaurant/Customer.java
new file mode 100644
index 0000000..a242d04
--- /dev/null
+++ b/Restaurant/Customer.java
@@ -0,0 +1,35 @@
+public class Customer {
+    private int customerNumber;
+    private String name;
+    private Address address;
+    public double latitude;
+    public double longitude;
+    public String writtenAddress;
+
+    public Customer(String name , Address address) {
+        this.customerNumber = generateUniqueCustomerNumber();
+        this.name = "";
+        this.address = new Address(latitude, longitude, writtenAddress);
+    }
+
+    private static int nextCustomerNumber = 1;
+    private int generateUniqueCustomerNumber() {
+        return nextCustomerNumber++;
+    }
+
+    public int getCustomerNumber() {
+        return customerNumber;
+    }
+    public String getName() {
+        return name;
+    }
+    public void setName(String name) {
+        this.name = name;
+    }
+    public Address getAddress() {
+        return address;
+    }
+    public void setAddress(Address address) {
+        this.address = address;
+    }
+}
\ No newline at end of file
diff --git a/Restaurant/Food.java b/Restaurant/Food.java
new file mode 100644
index 0000000..a459726
--- /dev/null
+++ b/Restaurant/Food.java
@@ -0,0 +1,21 @@
+import java.util.Vector;
+public class Food {
+    private String name;
+    private int price;
+    private static Vector<Food> menu = new Vector<>();
+
+    public Food(String name, int price) {
+        this.name = name;
+        this.price = price;
+        menu.add(this);
+    }
+    public String getName() {
+        return name;
+    }
+    public int getPrice() {
+        return price;
+    }
+    public static Vector<Food> getMenu() {
+        return menu;
+    }
+}
diff --git a/Restaurant/Invoice.java b/Restaurant/Invoice.java
new file mode 100644
index 0000000..ec21cf5
--- /dev/null
+++ b/Restaurant/Invoice.java
@@ -0,0 +1,50 @@
+import java.util.Vector;
+class Invoice {
+    private static final float taxRate = 0.094f;
+    private Customer customer;
+    private int state;
+    private Vector<Item> items;
+    private int price;
+    private Item item;
+
+    public Invoice(Customer customer) {
+        this.customer = customer;
+        this.state = -1;
+        this.items = new Vector<>();
+    }
+    public int getState(){
+        return state;
+    }
+    public Customer getCustomer(){
+        return customer;
+    }
+    public Vector<Item> getItems(){
+        return items;
+    }
+    public boolean addItem(Item item) {
+        if (state == -1) {
+            items.add(item);
+            return true;
+        }
+        return false;
+    }
+    public boolean removeItem(Item item) {
+        if (state == -1 && items.contains(item)) {
+            return items.remove(item);
+        }
+        return false;
+    }
+    public void nextStage() {
+        if (state < 2) {
+            state++;
+        }
+    }
+    public int getTotalPrice() {
+        double total = 0.0;
+        for (Item item : items) {
+            total += (item.getFood().getPrice()) * item.getCount();
+        }
+        double totalTax = total * taxRate;
+        return (int) Math.ceil(total + totalTax);
+    }
+}
\ No newline at end of file
diff --git a/Restaurant/Item.java b/Restaurant/Item.java
new file mode 100644
index 0000000..e09f930
--- /dev/null
+++ b/Restaurant/Item.java
@@ -0,0 +1,27 @@
+public class Item {
+    private Food food;
+    private int count;
+    private String description;
+    private int price;
+
+    public Item(Food food, int count, String description) {
+        this.food = food;
+        this.count = count;
+        this.description = description;
+
+    }
+    public Item(Food food, int count) {
+        this.food = food;
+        this.count = count;
+        this.description = "-";
+    }
+    public Food getFood() {
+        return food;
+    }
+    public int getCount() {
+        return count;
+    }
+    public String getDescription() {
+        return description;
+    }
+}
\ No newline at end of file
diff --git a/Restaurant/Main.java b/Restaurant/Main.java
new file mode 100644
index 0000000..9f081cf
--- /dev/null
+++ b/Restaurant/Main.java
@@ -0,0 +1,53 @@
+public class Main {
+    public static void main(String[] args) {
+        Address a1 = new Address(2, 3, "Lahijan");
+        Address a2 = new Address(5, 6, "Tehran");
+
+        System.out.println("\n--------------------------------------\n");
+        System.out.println("Distance From Address a1 to a2 is: " + a1.distanceFrom(a2));
+        System.out.println("\n--------------------------------------\n");
+
+        Customer c1 = new Customer("MAMAD", a1);
+        Customer c2 = new Customer("ALI", a2);
+
+        System.out.println("First Customer's ID: " + c1.getCustomerNumber());
+        System.out.println("Second Customer's ID: " + c2.getCustomerNumber());
+
+        Food f1 = new Food("BURGER", 130);
+        Food f2 = new Food("PIZZA", 200);
+        Food f3 = new Food("PASTA", 110);
+
+        System.out.println("\n--------------------------------------\n");
+
+        for (int i = 0; i < Food.getMenu().size(); i++) {
+            System.out.println("Food Name: " + Food.getMenu().get(i).getName());
+        }
+
+        System.out.println("\n--------------------------------------\n");
+
+        Item it1 = new Item(f1, 2);
+        Item it2 = new Item(f2, 3, "MORE SAUCE");
+        Item it3 = new Item(f3, 1);
+
+        Invoice inv = new Invoice(c1);
+
+        if (inv.addItem(it1) && inv.addItem(it2)) System.out.println("Items added successfully");
+        else System.out.println("Items could not be added");
+
+        if (inv.removeItem(it3)) System.out.println("Item removed successfully");
+        else System.out.println("Failed to remove item (item doesn't exist in invoice)");
+
+        inv.nextStage();
+
+        System.out.println("Current state: " + inv.getState());
+
+        System.out.println("\n--------------------------------------\n");
+
+        for (int i = 0; i < inv.getItems().size(); i++) {
+            Item it = inv.getItems().get(i);
+            System.out.println("Food Name: " + it.getFood().getName() + " | Food Description: " + it.getDescription());
+        }
+
+        System.out.println("Total price: " + inv.getTotalPrice());
+    }
+}
\ No newline at end of file