Merge branch 'master' of https://github.com/IneshAg/Python

Author: IneshAg

data_structures/linked_list/xor_linked_list.py

@@ -11,8 +11,7 @@
 [10, 20, 30]
 """
 
-# Note: 'from typing import Optional' is no longer needed
-# as we use the modern 'Node | None' syntax.
+# Note: 'from typing import Optional' is removed as we use the modern '|' syntax.
 
 
 class Node:
@@ -25,19 +24,26 @@ def __init__(self, value: int) -> None:
 class XORLinkedList:
     def __init__(self) -> None:
         """Initializes an empty XOR Linked List."""
+        # Use 'Node | None' instead of 'Optional[Node]' (per ruff UP045)
         self.head: Node | None = None
         self.tail: Node | None = None
         # id -> node map to simulate pointer references
         self._nodes: dict[int, Node] = {}
 
-    def _xor(self, a: Node | None, b: Node | None) -> int:
-        """Helper function to get the XOR of two node IDs."""
-        return (id(a) if a else 0) ^ (id(b) if b else 0)
+    def _xor(self, node_a: Node | None, node_b: Node | None) -> int:
+        """
+        Helper function to get the XOR of two node IDs (simulated addresses).
+        Names 'node_a' and 'node_b' are used for descriptive parameters.
+        """
+        id_a = id(node_a) if node_a else 0
+        id_b = id(node_b) if node_b else 0
+        return id_a ^ id_b
 
     def insert(self, value: int) -> None:
         """Inserts a value at the end of the list."""
         node = Node(value)
         self._nodes[id(node)] = node
+        node_id = id(node)
 
         if self.head is None:
             # If the list is empty, head and tail are the new node
@@ -51,7 +57,7 @@ def insert(self, value: int) -> None:
                 # its previous node ID with the new node's ID.
                 # self.tail.both was (prev_id ^ 0)
                 # self.tail.both becomes (prev_id ^ new_node_id)
-                self.tail.both ^= id(node)
+                self.tail.both ^= node_id
             self.tail = node
 
     def to_list(self) -> list[int]:
@@ -64,10 +70,11 @@ def to_list(self) -> list[int]:
             # Find next node's ID:
             # current.both = prev_id ^ next_id
             # so, next_id = prev_id ^ current.both
+            current_id = id(current)
             next_id = prev_id ^ current.both
 
             # Move forward
-            prev_id = id(current)
+            prev_id = current_id
             current = self._nodes.get(next_id)
         return result