Add delete_node functionality for linked list

data_structures/linked_list/delete_node.py

@@ -0,0 +1,75 @@
+from typing import Any
+
+
+class CannotDeleteTailError(Exception):
+    pass
+
+
+class Node:
+    def __init__(self, data: Any) -> None:
+        self.data: Any = data
+        self.next_node: Node | None = None
+
+    def __iter__(self):
+        node = self
+        while node:
+            yield node.data
+            node = node.next_node
+
+    def delete(self) -> None:
+        """
+        Deletes the current node from the linked list by
+        copying the data from the next node
+        and bypassing the next node.
+
+        It is assumed that the node to be deleted is not the tail node.
+
+        >>> root_node = Node(1)
+        >>> root_node.next_node = Node(2)
+        >>> root_node.next_node.next_node = Node(3)
+        >>> root_node.next_node.delete()  # delete node with value 2
+        >>> list(root_node)
+        [1, 3]
+        """
+        if self.next_node is None:
+            raise CannotDeleteTailError("Cannot delete the tail node with this method.")
+
+        # Copy data from the next node to the current node
+        self.data = self.next_node.data
+        # Bypass the next node
+        self.next_node = self.next_node.next_node
+
+
+if __name__ == "__main__":
+    # Example 1
+    root_node = Node(1)
+    root_node.next_node = Node(2)
+    root_node.next_node.next_node = Node(3)
+    root_node.next_node.next_node.next_node = Node(4)
+
+    # Delete node with value 3
+    node_to_delete = root_node.next_node.next_node
+    node_to_delete.delete()  # deletes node 3
+
+    print(list(root_node))  # [1, 2, 4]
+
+    # Example 2: Deleting the second node
+    root_node = Node(10)
+    root_node.next_node = Node(20)
+    root_node.next_node.next_node = Node(30)
+
+    # Delete node with value 20
+    node_to_delete = root_node.next_node
+    node_to_delete.delete()  # deletes node 20
+
+    print(list(root_node))  # [10, 30]
+
+    # Example 3: Trying to delete the tail node should raise an error
+    root_node = Node(5)
+    root_node.next_node = Node(6)
+    tail_node = root_node.next_node
+
+    try:
+        tail_node.delete()  # Cannot delete the tail node
+    except CannotDeleteTailError as e:
+        print(e)  # Cannot delete the tail node with this method