diff --git a/data_structures/hashing/hash_table_with_linked_list.py b/data_structures/hashing/hash_table_with_linked_list.py
index f404c5251246..c8dffa30b8e8 100644
--- a/data_structures/hashing/hash_table_with_linked_list.py
+++ b/data_structures/hashing/hash_table_with_linked_list.py
@@ -8,7 +8,7 @@ def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
 
     def _set_value(self, key, data):
-        self.values[key] = deque([]) if self.values[key] is None else self.values[key]
+        self.values[key] = deque() if self.values[key] is None else self.values[key]
         self.values[key].appendleft(data)
         self._keys[key] = self.values[key]
 
diff --git a/searches/hill_climbing.py b/searches/hill_climbing.py
index 689b7e5cca8f..8e77e4de35cd 100644
--- a/searches/hill_climbing.py
+++ b/searches/hill_climbing.py
@@ -1,5 +1,6 @@
 # https://en.wikipedia.org/wiki/Hill_climbing
 import math
+from collections.abc import Callable
 
 
 class SearchProblem:
@@ -8,7 +9,13 @@ class SearchProblem:
     The interface will be illustrated using the example of mathematical function.
     """
 
-    def __init__(self, x: int, y: int, step_size: int, function_to_optimize):
+    def __init__(
+        self,
+        x: int,
+        y: int,
+        step_size: int,
+        function_to_optimize: Callable[[int, int], int | float],
+    ) -> None:
         """
         The constructor of the search problem.
 
@@ -22,7 +29,7 @@ def __init__(self, x: int, y: int, step_size: int, function_to_optimize):
         self.step_size = step_size
         self.function = function_to_optimize
 
-    def score(self) -> int:
+    def score(self) -> int | float:
         """
         Returns the output of the function called with current x and y coordinates.
         >>> def test_function(x, y):
@@ -34,7 +41,7 @@ def score(self) -> int:
         """
         return self.function(self.x, self.y)
 
-    def get_neighbors(self):
+    def get_neighbors(self) -> list["SearchProblem"]:
         """
         Returns a list of coordinates of neighbors adjacent to the current coordinates.
 
@@ -58,13 +65,13 @@ def get_neighbors(self):
             )
         ]
 
-    def __hash__(self):
+    def __hash__(self) -> int:
         """
         hash the string representation of the current search state.
         """
         return hash(str(self))
 
-    def __eq__(self, obj):
+    def __eq__(self, obj: object) -> bool:
         """
         Check if the 2 objects are equal.
         """
@@ -72,7 +79,7 @@ def __eq__(self, obj):
             return hash(str(self)) == hash(str(obj))
         return False
 
-    def __str__(self):
+    def __str__(self) -> str:
         """
         string representation of the current search state.
         >>> str(SearchProblem(0, 0, 1, None))
@@ -84,7 +91,7 @@ def __str__(self):
 
 
 def hill_climbing(
-    search_prob,
+    search_prob: SearchProblem,
     find_max: bool = True,
     max_x: float = math.inf,
     min_x: float = -math.inf,