diff --git a/app/main.py b/app/main.py
index fa56336e..906713a3 100644
--- a/app/main.py
+++ b/app/main.py
@@ -1 +1,34 @@
-# write your code here
+from __future__ import annotations
+
+
+class Animal:
+    alive = []
+
+    def __init__(self,
+                 name: str,
+                 health: int = 100,
+                 hidden: bool = False) -> None:
+        self.name = name
+        self.health = health
+        self.hidden = hidden
+        Animal.alive.append(self)
+
+    def __repr__(self) -> str:
+        return (
+            f"{{Name: {self.name}, "
+            f"Health: {self.health}, "
+            f"Hidden: {self.hidden}}}"
+        )
+
+
+class Herbivore(Animal):
+    def hide(self) -> None:
+        self.hidden = not self.hidden
+
+
+class Carnivore(Animal):
+    def bite(self, other: Animal) -> None:
+        if isinstance(other, Herbivore) and not other.hidden:
+            other.health -= 50
+            if other.health <= 0 and other in Animal.alive:
+                Animal.alive.remove(other)