From 236de629dc96793bf7f63190d56c167d3cfdbdb4 Mon Sep 17 00:00:00 2001
From: shaghayeghfar <146011477+shaghayeghfar@users.noreply.github.com>
Date: Tue, 13 Oct 2026 20:58:20 +0100
Subject: [PATCH 1/2] implement_linked_list task was complegted

---
 Sprint-2/implement_linked_list/linked_list.py | 53 +++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/Sprint-2/implement_linked_list/linked_list.py b/Sprint-2/implement_linked_list/linked_list.py
index e69de29b..765c131b 100644
--- a/Sprint-2/implement_linked_list/linked_list.py
+++ b/Sprint-2/implement_linked_list/linked_list.py
@@ -0,0 +1,53 @@
+class Node:
+    def __init__(self, value):
+        self.value = value
+        self.next = None
+        self.previous = None
+
+
+class LinkedList:
+    def __init__(self):
+        self.head = None
+        self.tail = None
+
+    def push_head(self, value):
+        new_node = Node(value)
+
+        if self.head is None:
+            self.head = new_node
+            self.tail = new_node
+        else:
+            new_node.next = self.head
+            self.head.previous = new_node
+            self.head = new_node
+
+        return new_node
+
+    def pop_tail(self):
+        if self.tail is None:
+            raise IndexError("Cannot pop from an empty list")
+
+        removed_node = self.tail
+
+        if self.head == self.tail:
+            self.head = None
+            self.tail = None
+        else:
+            self.tail = self.tail.previous
+            self.tail.next = None
+
+        return removed_node.value
+
+    def remove(self, node):
+        if node.previous is None:
+            self.head = node.next
+        else:
+            node.previous.next = node.next
+
+        if node.next is None:
+            self.tail = node.previous
+        else:
+            node.next.previous = node.previous
+
+        node.next = None
+        node.previous = None
\ No newline at end of file

From 23b28812ff1605412f2327c91d15fd6778682825 Mon Sep 17 00:00:00 2001
From: shaghayeghfar <146011477+shaghayeghfar@users.noreply.github.com>
Date: Wed, 14 Oct 2026 10:34:40 +0100
Subject: [PATCH 2/2]  the changes were done

---
 Sprint-2/implement_linked_list/linked_list.py | 35 +++++++++----------
 1 file changed, 17 insertions(+), 18 deletions(-)

diff --git a/Sprint-2/implement_linked_list/linked_list.py b/Sprint-2/implement_linked_list/linked_list.py
index 765c131b..65b11105 100644
--- a/Sprint-2/implement_linked_list/linked_list.py
+++ b/Sprint-2/implement_linked_list/linked_list.py
@@ -1,16 +1,21 @@
+from typing import Optional
+
+
 class Node:
-    def __init__(self, value):
-        self.value = value
-        self.next = None
-        self.previous = None
+    __slots__ = ("value", "next", "previous")
+
+    def __init__(self, value: str) -> None:
+        self.value: str = value
+        self.next: Optional[Node] = None
+        self.previous: Optional[Node] = None
 
 
 class LinkedList:
-    def __init__(self):
-        self.head = None
-        self.tail = None
+    def __init__(self) -> None:
+        self.head: Optional[Node] = None
+        self.tail: Optional[Node] = None
 
-    def push_head(self, value):
+    def push_head(self, value: str) -> Node:
         new_node = Node(value)
 
         if self.head is None:
@@ -23,22 +28,16 @@ def push_head(self, value):
 
         return new_node
 
-    def pop_tail(self):
+    def pop_tail(self) -> str:
         if self.tail is None:
             raise IndexError("Cannot pop from an empty list")
 
         removed_node = self.tail
-
-        if self.head == self.tail:
-            self.head = None
-            self.tail = None
-        else:
-            self.tail = self.tail.previous
-            self.tail.next = None
+        self.remove(removed_node)
 
         return removed_node.value
 
-    def remove(self, node):
+    def remove(self, node: Node) -> None:
         if node.previous is None:
             self.head = node.next
         else:
@@ -50,4 +49,4 @@ def remove(self, node):
             node.next.previous = node.previous
 
         node.next = None
-        node.previous = None
\ No newline at end of file
+        node.previous = None