diff --git a/app/main.py b/app/main.py
index 626f41cf..7bfbf189 100644
--- a/app/main.py
+++ b/app/main.py
@@ -1,34 +1,129 @@
+from dataclasses import dataclass
+
+
+class ValidateFieldError(Exception):
+    pass
+
+
+@dataclass
 class Deck:
-    def __init__(self, row, column, is_alive=True):
-        pass
+    row: int
+    column: int
+    is_alive: bool = True
+    status = u"\u25A1"
 
 
 class Ship:
-    def __init__(self, start, end, is_drowned=False):
-        # Create decks and save them to a list `self.decks`
-        pass
+    def __init__(self, start: tuple, end: tuple) -> None:
+        self.start = start
+        self.end = end
+        self.is_drowned = False
+        self.decks = []
 
-    def get_deck(self, row, column):
-        # Find the corresponding deck in the list
-        pass
+    def get_deck(self, row: int, column: int) -> Deck | None:
+        for deck in self.decks:
+            if deck.row == row and deck.column == column:
+                return deck
+        return
 
-    def fire(self, row, column):
-        # Change the `is_alive` status of the deck
-        # And update the `is_drowned` value if it's needed
-        pass
+    def fire(self, row: int, column: int) -> None:
+        deck = self.get_deck(row, column)
+        if deck:
+            deck.is_alive = False
+            deck.status = "*"
+            if not any(deck.is_alive for deck in self.decks):
+                self.is_drowned = True
+                for deck in self.decks:
+                    deck.status = "x"
+
+    def create_new_deck(self) -> None:
+        if self.start[0] == self.end[0]:
+            decks_number = self.end[1] - self.start[1] + 1
+            for ship_deck in range(decks_number):
+                created_deck = Deck(self.start[0], self.start[1] + ship_deck)
+                self.decks.append(created_deck)
+        else:
+            decks_number = self.end[0] - self.start[0] + 1
+            for ship_deck in range(decks_number):
+                created_deck = Deck(self.start[0] + ship_deck, self.start[1])
+                self.decks.append(created_deck)
+
+    def get_neighbors(self) -> list:
+        neighbors = []
+        for deck in self.decks:
+            x, y = deck.row, deck.column
+            for row in range(-1, 2):
+                for column in range(-1, 2):
+                    if row != 0 or column != 0:
+                        neighbors_x, neighbors_y = x + row, y + column
+                        if 0 <= neighbors_x < 10 and 0 <= neighbors_y < 10:
+                            neighbors.append((neighbors_x, neighbors_y))
+        return neighbors
 
 
 class Battleship:
-    def __init__(self, ships):
-        # Create a dict `self.field`.
-        # Its keys are tuples - the coordinates of the non-empty cells,
-        # A value for each cell is a reference to the ship
-        # which is located in it
-        pass
-
-    def fire(self, location: tuple):
-        # This function should check whether the location
-        # is a key in the `self.field`
-        # If it is, then it should check if this cell is the last alive
-        # in the ship or not.
-        pass
+    def __init__(self, ships: list[tuple]) -> None:
+        self.ships = ships
+        self.field = {}
+        for ship in ships:
+            created_ship = Ship(ship[0], ship[1])
+            created_ship.create_new_deck()
+            for deck in created_ship.decks:
+                self.field[(deck.row, deck.column)] = created_ship
+        if not self._validate_field():
+            raise ValidateFieldError
+
+    def fire(self, location: tuple) -> str:
+        battleship = self.field.get(location)
+        if battleship:
+            battleship.fire(*location)
+            if battleship.is_drowned:
+                return "Sunk!"
+            return "Hit!"
+        return "Miss!"
+
+    def print_field(self) -> None:
+        for row in range(10):
+            output = ""
+            for column in range(10):
+                deck = self.field.get((row, column))
+                if deck:
+                    deck = deck.get_deck(row, column)
+                    output += f"{deck.status}  "
+                    continue
+                output += "~  "
+            print(output)
+
+    def _validate_field(self) -> bool:
+        verdict = True
+
+        ships = list(set(self.field.values()))
+        if len(ships) != 10:
+            verdict = False
+
+        number_of_decks = {}
+        for ship in ships:
+            if number_of_decks.get(len(ship.decks)):
+                number_of_decks[len(ship.decks)] += 1
+            else:
+                number_of_decks[len(ship.decks)] = 1
+        if not all(
+                [
+                    number_of_decks[1] == 4,
+                    number_of_decks[2] == 3,
+                    number_of_decks[3] == 2,
+                    number_of_decks[4] == 1
+                ]
+        ):
+            verdict = False
+
+        for first_ship in ships:
+            for second_ship in ships:
+                if first_ship != second_ship:
+                    occupied_coordinate = first_ship.get_neighbors()
+                    for deck in second_ship.decks:
+                        x, y = deck.row, deck.column
+                        if (x, y) in occupied_coordinate:
+                            verdict = False
+
+        return verdict