TheAlgorithms · cclauss · Nov 6, 2022 · Nov 1, 2022 · Nov 2, 2022 · Nov 2, 2022
diff --git a/.flake8 b/.flake8
@@ -6,3 +6,4 @@ extend-ignore =
     # Formatting style for `black`
     E203  # Whitespace before ':'
     W503  # Line break occurred before a binary operator
+    B023  # Function definition does not bind loop variable
diff --git a/boolean_algebra/quine_mc_cluskey.py b/boolean_algebra/quine_mc_cluskey.py
@@ -1,15 +1,16 @@
 from __future__ import annotations
 
 from collections.abc import Sequence
+from typing import Literal
 
 
-def compare_string(string1: str, string2: str) -> str:
+def compare_string(string1: str, string2: str) -> str | Literal[False]:
     """
     >>> compare_string('0010','0110')
     '0_10'
 
     >>> compare_string('0110','1101')
-    'X'
+    False
     """
     list1 = list(string1)
     list2 = list(string2)
@@ -19,7 +20,7 @@ def compare_string(string1: str, string2: str) -> str:
             count += 1
             list1[i] = "_"
     if count > 1:
-        return "X"
+        return False
     else:
         return "".join(list1)
 

diff --git a/ciphers/shuffled_shift_cipher.py b/ciphers/shuffled_shift_cipher.py
@@ -42,7 +42,7 @@ def __str__(self) -> str:
         """
         :return: passcode of the cipher object
         """
-        return "Passcode is: " + "".join(self.__passcode)
+        return "".join(self.__passcode)
 
     def __neg_pos(self, iterlist: list[int]) -> list[int]:
         """

diff --git a/computer_vision/harris_corner.py b/computer_vision/harris_corner.py
@@ -22,8 +22,7 @@ def __init__(self, k: float, window_size: int):
             raise ValueError("invalid k value")
 
     def __str__(self) -> str:
-
-        return f"Harris Corner  detection with k : {self.k}"
+        return self.k
 
     def detect(self, img_path: str) -> tuple[cv2.Mat, list[list[int]]]:
 

diff --git a/data_structures/binary_tree/segment_tree_other.py b/data_structures/binary_tree/segment_tree_other.py
@@ -16,8 +16,8 @@ def __init__(self, start, end, val, left=None, right=None):
         self.left = left
         self.right = right
 
-    def __str__(self):
-        return f"val: {self.val}, start: {self.start}, end: {self.end}"
+    def __repr__(self):
+        return f"<val={self.val} start={self.start} end={self.end}>"
 
 
 class SegmentTree:
@@ -27,29 +27,29 @@ class SegmentTree:
     >>> for node in num_arr.traverse():
     ...     print(node)
     ...
-    val: 15, start: 0, end: 4
-    val: 8, start: 0, end: 2
-    val: 7, start: 3, end: 4
-    val: 3, start: 0, end: 1
-    val: 5, start: 2, end: 2
-    val: 3, start: 3, end: 3
-    val: 4, start: 4, end: 4
-    val: 2, start: 0, end: 0
-    val: 1, start: 1, end: 1
+    <val=15 start=0 end=4>
+    <val=8 start=0 end=2>
+    <val=7 start=3 end=4>
+    <val=3 start=0 end=1>
+    <val=5 start=2 end=2>
+    <val=3 start=3 end=3>
+    <val=4 start=4 end=4>
+    <val=2 start=0 end=0>
+    <val=1 start=1 end=1>
     >>>
     >>> num_arr.update(1, 5)
     >>> for node in num_arr.traverse():
     ...     print(node)
     ...
-    val: 19, start: 0, end: 4
-    val: 12, start: 0, end: 2
-    val: 7, start: 3, end: 4
-    val: 7, start: 0, end: 1
-    val: 5, start: 2, end: 2
-    val: 3, start: 3, end: 3
-    val: 4, start: 4, end: 4
-    val: 2, start: 0, end: 0
-    val: 5, start: 1, end: 1
+    <val=19 start=0 end=4>
+    <val=12 start=0 end=2>
+    <val=7 start=3 end=4>
+    <val=7 start=0 end=1>
+    <val=5 start=2 end=2>
+    <val=3 start=3 end=3>
+    <val=4 start=4 end=4>
+    <val=2 start=0 end=0>
+    <val=5 start=1 end=1>
     >>>
     >>> num_arr.query_range(3, 4)
     7
@@ -62,29 +62,29 @@ class SegmentTree:
     >>> for node in max_arr.traverse():
     ...     print(node)
     ...
-    val: 5, start: 0, end: 4
-    val: 5, start: 0, end: 2
-    val: 4, start: 3, end: 4
-    val: 2, start: 0, end: 1
-    val: 5, start: 2, end: 2
-    val: 3, start: 3, end: 3
-    val: 4, start: 4, end: 4
-    val: 2, start: 0, end: 0
-    val: 1, start: 1, end: 1
+    <val=5 start=0 end=4>
+    <val=5 start=0 end=2>
+    <val=4 start=3 end=4>
+    <val=2 start=0 end=1>
+    <val=5 start=2 end=2>
+    <val=3 start=3 end=3>
+    <val=4 start=4 end=4>
+    <val=2 start=0 end=0>
+    <val=1 start=1 end=1>
     >>>
     >>> max_arr.update(1, 5)
     >>> for node in max_arr.traverse():
     ...     print(node)
     ...
-    val: 5, start: 0, end: 4
-    val: 5, start: 0, end: 2
-    val: 4, start: 3, end: 4
-    val: 5, start: 0, end: 1
-    val: 5, start: 2, end: 2
-    val: 3, start: 3, end: 3
-    val: 4, start: 4, end: 4
-    val: 2, start: 0, end: 0
-    val: 5, start: 1, end: 1
+    <val=5 start=0 end=4>
+    <val=5 start=0 end=2>
+    <val=4 start=3 end=4>
+    <val=5 start=0 end=1>
+    <val=5 start=2 end=2>
+    <val=3 start=3 end=3>
+    <val=4 start=4 end=4>
+    <val=2 start=0 end=0>
+    <val=5 start=1 end=1>
     >>>
     >>> max_arr.query_range(3, 4)
     4
@@ -97,29 +97,29 @@ class SegmentTree:
     >>> for node in min_arr.traverse():
     ...     print(node)
     ...
-    val: 1, start: 0, end: 4
-    val: 1, start: 0, end: 2
-    val: 3, start: 3, end: 4
-    val: 1, start: 0, end: 1
-    val: 5, start: 2, end: 2
-    val: 3, start: 3, end: 3
-    val: 4, start: 4, end: 4
-    val: 2, start: 0, end: 0
-    val: 1, start: 1, end: 1
+    <val=1 start=0 end=4>
+    <val=1 start=0 end=2>
+    <val=3 start=3 end=4>
+    <val=1 start=0 end=1>
+    <val=5 start=2 end=2>
+    <val=3 start=3 end=3>
+    <val=4 start=4 end=4>
+    <val=2 start=0 end=0>
+    <val=1 start=1 end=1>
     >>>
     >>> min_arr.update(1, 5)
     >>> for node in min_arr.traverse():
     ...     print(node)
     ...
-    val: 2, start: 0, end: 4
-    val: 2, start: 0, end: 2
-    val: 3, start: 3, end: 4
-    val: 2, start: 0, end: 1
-    val: 5, start: 2, end: 2
-    val: 3, start: 3, end: 3
-    val: 4, start: 4, end: 4
-    val: 2, start: 0, end: 0
-    val: 5, start: 1, end: 1
+    <val=2 start=0 end=4>
+    <val=2 start=0 end=2>
+    <val=3 start=3 end=4>
+    <val=2 start=0 end=1>
+    <val=5 start=2 end=2>
+    <val=3 start=3 end=3>
+    <val=4 start=4 end=4>
+    <val=2 start=0 end=0>
+    <val=5 start=1 end=1>
     >>>
     >>> min_arr.query_range(3, 4)
     3

diff --git a/data_structures/binary_tree/wavelet_tree.py b/data_structures/binary_tree/wavelet_tree.py
@@ -24,11 +24,11 @@ def __repr__(self) -> str:
         """
         >>> node = Node(length=27)
         >>> repr(node)
-        'min_value: -1, max_value: -1'
+        '<min_value=-1 max_value=-1>'
         >>> repr(node) == str(node)
         True
         """
-        return f"min_value: {self.minn}, max_value: {self.maxx}"
+        return f"<min_value={self.minn} max_value={self.maxx}>"
 
 
 def build_tree(arr: list[int]) -> Node | None:
@@ -37,7 +37,7 @@ def build_tree(arr: list[int]) -> Node | None:
     of the constructed tree
 
     >>> build_tree(test_array)
-    min_value: 0, max_value: 9
+    <min_value=0 max_value=9>
     """
     root = Node(len(arr))
     root.minn, root.maxx = min(arr), max(arr)

diff --git a/data_structures/linked_list/doubly_linked_list.py b/data_structures/linked_list/doubly_linked_list.py
@@ -159,7 +159,7 @@ def delete(self, data) -> str:
             if current.next:
                 current = current.next
             else:  # We have reached the end an no value matches
-                return "No data matching given value"
+                raise ValueError("No data matching given value")
 
         if current == self.head:
             self.delete_head()

diff --git a/data_structures/queue/double_ended_queue.py b/data_structures/queue/double_ended_queue.py
@@ -426,7 +426,7 @@ def __repr__(self) -> str:
             values_list.append(aux.val)
             aux = aux.next
 
-        return "[" + ", ".join(repr(val) for val in values_list) + "]"
+        return f"[{', '.join(repr(val) for val in values_list)}]"
 
 
 if __name__ == "__main__":

diff --git a/genetic_algorithm/basic_string.py b/genetic_algorithm/basic_string.py
@@ -129,9 +129,7 @@ def select(parent_1: tuple[str, float]) -> list[str]:
             child_n = int(parent_1[1] * 100) + 1
             child_n = 10 if child_n >= 10 else child_n
             for _ in range(child_n):
-                parent_2 = population_score[  # noqa: B023
-                    random.randint(0, N_SELECTED)
-                ][0]
+                parent_2 = population_score[random.randint(0, N_SELECTED)][0]
 
                 child_1, child_2 = crossover(parent_1[0], parent_2)
                 # Append new string to the population list.

diff --git a/graphs/breadth_first_search_shortest_path.py b/graphs/breadth_first_search_shortest_path.py
@@ -58,7 +58,9 @@ def shortest_path(self, target_vertex: str) -> str:
 
         Case 1 - No path is found.
         >>> g.shortest_path("Foo")
-        'No path from vertex:G to vertex:Foo'
+        Traceback (most recent call last):
+            ...
+        ValueError: No path from vertex: G to vertex: Foo
 
         Case 2 - The path is found.
         >>> g.shortest_path("D")
@@ -71,7 +73,9 @@ def shortest_path(self, target_vertex: str) -> str:
 
         target_vertex_parent = self.parent.get(target_vertex)
         if target_vertex_parent is None:
-            return f"No path from vertex:{self.source_vertex} to vertex:{target_vertex}"
+            raise ValueError(
+                f"No path from vertex: {self.source_vertex} to vertex: {target_vertex}"
+            )
 
         return self.shortest_path(target_vertex_parent) + f"->{target_vertex}"
 

diff --git a/graphs/page_rank.py b/graphs/page_rank.py
@@ -27,7 +27,7 @@ def add_outbound(self, node):
         self.outbound.append(node)
 
     def __repr__(self):
-        return f"Node {self.name}: Inbound: {self.inbound} ; Outbound: {self.outbound}"
+        return f"<node={self.name} inbound={self.inbound} outbound={self.outbound}>"
 
 
 def page_rank(nodes, limit=3, d=0.85):

diff --git a/linear_algebra/src/polynom_for_points.py b/linear_algebra/src/polynom_for_points.py
@@ -113,7 +113,7 @@ def points_to_polynomial(coordinates: list[list[int]]) -> str:
     elif check == 2:
         return solved
     else:
-        return "The program cannot work out a fitting polynomial."
+        raise ValueError("The program cannot work out a fitting polynomial.")
 
 
 if __name__ == "__main__":

diff --git a/maths/monte_carlo_dice.py b/maths/monte_carlo_dice.py
@@ -13,9 +13,6 @@ def __init__(self):
     def roll(self):
         return random.choice(self.sides)
 
-    def _str_(self):
-        return "Fair Dice"
-
 
 def throw_dice(num_throws: int, num_dice: int = 2) -> list[float]:
     """

diff --git a/matrix/cramers_rule_2x2.py b/matrix/cramers_rule_2x2.py
@@ -2,7 +2,7 @@
 # https://en.wikipedia.org/wiki/Cramer%27s_rule
 
 
-def cramers_rule_2x2(equation1: list[int], equation2: list[int]) -> str:
+def cramers_rule_2x2(equation1: list[int], equation2: list[int]) -> tuple[float]:
     """
     Solves the system of linear equation in 2 variables.
     :param: equation1: list of 3 numbers
@@ -14,13 +14,13 @@ def cramers_rule_2x2(equation1: list[int], equation2: list[int]) -> str:
     determinant_y = [[a1, d1], [a2, d2]]
 
     >>> cramers_rule_2x2([2, 3, 0], [5, 1, 0])
-    'Trivial solution. (Consistent system) x = 0 and y = 0'
+    (0, 0)
     >>> cramers_rule_2x2([0, 4, 50], [2, 0, 26])
-    'Non-Trivial Solution (Consistent system) x = 13.0, y = 12.5'
+    (13.0, 12.5)
     >>> cramers_rule_2x2([11, 2, 30], [1, 0, 4])
-    'Non-Trivial Solution (Consistent system) x = 4.0, y = -7.0'
+    (4.0, -7.0)
     >>> cramers_rule_2x2([4, 7, 1], [1, 2, 0])
-    'Non-Trivial Solution (Consistent system) x = 2.0, y = -1.0'
+    (2.0, -1.0)
 
     >>> cramers_rule_2x2([1, 2, 3], [2, 4, 6])
     Traceback (most recent call last):
@@ -75,8 +75,10 @@ def cramers_rule_2x2(equation1: list[int], equation2: list[int]) -> str:
             raise ValueError("No solution. (Inconsistent system)")
     else:
         if determinant_x == determinant_y == 0:
-            return "Trivial solution. (Consistent system) x = 0 and y = 0"
+            # Trivial solution (Inconsistent system)
+            return (0, 0)
         else:
             x = determinant_x / determinant
             y = determinant_y / determinant
-            return f"Non-Trivial Solution (Consistent system) x = {x}, y = {y}"
+            # Non-Trivial Solution (Consistent system)
+            return (x, y)