Updated Stack (#2414)

* * Added type hints
* Added test
* Formated code

* updating DIRECTORY.md

* Update stack.py

* Test error conditions for pop, peek, and

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Co-authored-by: Christian Clauss <cclauss@me.com>

DIRECTORY.md

@@ -24,6 +24,9 @@
   * [Sudoku](https://github.com/TheAlgorithms/Python/blob/master/backtracking/sudoku.py)
   * [Sum Of Subsets](https://github.com/TheAlgorithms/Python/blob/master/backtracking/sum_of_subsets.py)
 
+## Bit Manipulation
+  * [Binary Or Operator](https://github.com/TheAlgorithms/Python/blob/master/bit_manipulation/binary_or_operator.py)
+
 ## Blockchain
   * [Chinese Remainder Theorem](https://github.com/TheAlgorithms/Python/blob/master/blockchain/chinese_remainder_theorem.py)
   * [Diophantine Equation](https://github.com/TheAlgorithms/Python/blob/master/blockchain/diophantine_equation.py)
@@ -50,6 +53,7 @@
   * [Deterministic Miller Rabin](https://github.com/TheAlgorithms/Python/blob/master/ciphers/deterministic_miller_rabin.py)
   * [Diffie](https://github.com/TheAlgorithms/Python/blob/master/ciphers/diffie.py)
   * [Elgamal Key Generator](https://github.com/TheAlgorithms/Python/blob/master/ciphers/elgamal_key_generator.py)
+  * [Enigma Machine2](https://github.com/TheAlgorithms/Python/blob/master/ciphers/enigma_machine2.py)
   * [Hill Cipher](https://github.com/TheAlgorithms/Python/blob/master/ciphers/hill_cipher.py)
   * [Mixed Keyword Cypher](https://github.com/TheAlgorithms/Python/blob/master/ciphers/mixed_keyword_cypher.py)
   * [Morse Code Implementation](https://github.com/TheAlgorithms/Python/blob/master/ciphers/morse_code_implementation.py)
@@ -105,6 +109,7 @@
     * [Segment Tree Other](https://github.com/TheAlgorithms/Python/blob/master/data_structures/binary_tree/segment_tree_other.py)
     * [Treap](https://github.com/TheAlgorithms/Python/blob/master/data_structures/binary_tree/treap.py)
   * Disjoint Set
+    * [Alternate Disjoint Set](https://github.com/TheAlgorithms/Python/blob/master/data_structures/disjoint_set/alternate_disjoint_set.py)
     * [Disjoint Set](https://github.com/TheAlgorithms/Python/blob/master/data_structures/disjoint_set/disjoint_set.py)
   * Hashing
     * [Double Hash](https://github.com/TheAlgorithms/Python/blob/master/data_structures/hashing/double_hash.py)
@@ -419,6 +424,7 @@
   * [Sum Of Geometric Progression](https://github.com/TheAlgorithms/Python/blob/master/maths/sum_of_geometric_progression.py)
   * [Test Prime Check](https://github.com/TheAlgorithms/Python/blob/master/maths/test_prime_check.py)
   * [Trapezoidal Rule](https://github.com/TheAlgorithms/Python/blob/master/maths/trapezoidal_rule.py)
+  * [Ugly Numbers](https://github.com/TheAlgorithms/Python/blob/master/maths/ugly_numbers.py)
   * [Volume](https://github.com/TheAlgorithms/Python/blob/master/maths/volume.py)
   * [Zellers Congruence](https://github.com/TheAlgorithms/Python/blob/master/maths/zellers_congruence.py)
 
@@ -474,6 +480,7 @@
   * [Sdes](https://github.com/TheAlgorithms/Python/blob/master/other/sdes.py)
   * [Sierpinski Triangle](https://github.com/TheAlgorithms/Python/blob/master/other/sierpinski_triangle.py)
   * [Tower Of Hanoi](https://github.com/TheAlgorithms/Python/blob/master/other/tower_of_hanoi.py)
+  * [Triplet Sum](https://github.com/TheAlgorithms/Python/blob/master/other/triplet_sum.py)
   * [Two Sum](https://github.com/TheAlgorithms/Python/blob/master/other/two_sum.py)
   * [Word Patterns](https://github.com/TheAlgorithms/Python/blob/master/other/word_patterns.py)
 
@@ -600,6 +607,12 @@
     * [Solution42](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_42/solution42.py)
   * Problem 43
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_43/sol1.py)
+  * Problem 44
+    * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_44/sol1.py)
+  * Problem 45
+    * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_45/sol1.py)
+  * Problem 46
+    * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_46/sol1.py)
   * Problem 47
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_47/sol1.py)
   * Problem 48
@@ -608,10 +621,14 @@
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_52/sol1.py)
   * Problem 53
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_53/sol1.py)
+  * Problem 55
+    * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_55/sol1.py)
   * Problem 551
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_551/sol1.py)
   * Problem 56
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_56/sol1.py)
+  * Problem 63
+    * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_63/sol1.py)
   * Problem 67
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_67/sol1.py)
   * Problem 76
@@ -673,7 +690,6 @@
   * [Recursive Insertion Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/recursive_insertion_sort.py)
   * [Selection Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/selection_sort.py)
   * [Shell Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/shell_sort.py)
-  * [Sleep Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/sleep_sort.py)
   * [Stooge Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/stooge_sort.py)
   * [Strand Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/strand_sort.py)
   * [Tim Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/tim_sort.py)
@@ -685,6 +701,7 @@
 ## Strings
   * [Aho-Corasick](https://github.com/TheAlgorithms/Python/blob/master/strings/aho-corasick.py)
   * [Boyer Moore Search](https://github.com/TheAlgorithms/Python/blob/master/strings/boyer_moore_search.py)
+  * [Capitalize](https://github.com/TheAlgorithms/Python/blob/master/strings/capitalize.py)
   * [Check Anagrams](https://github.com/TheAlgorithms/Python/blob/master/strings/check_anagrams.py)
   * [Check Pangram](https://github.com/TheAlgorithms/Python/blob/master/strings/check_pangram.py)
   * [Is Palindrome](https://github.com/TheAlgorithms/Python/blob/master/strings/is_palindrome.py)
@@ -715,6 +732,7 @@
   * [Emails From Url](https://github.com/TheAlgorithms/Python/blob/master/web_programming/emails_from_url.py)
   * [Fetch Bbc News](https://github.com/TheAlgorithms/Python/blob/master/web_programming/fetch_bbc_news.py)
   * [Fetch Github Info](https://github.com/TheAlgorithms/Python/blob/master/web_programming/fetch_github_info.py)
+  * [Fetch Jobs](https://github.com/TheAlgorithms/Python/blob/master/web_programming/fetch_jobs.py)
   * [Get Imdb Top 250 Movies Csv](https://github.com/TheAlgorithms/Python/blob/master/web_programming/get_imdb_top_250_movies_csv.py)
   * [Get Imdbtop](https://github.com/TheAlgorithms/Python/blob/master/web_programming/get_imdbtop.py)
   * [Slack Message](https://github.com/TheAlgorithms/Python/blob/master/web_programming/slack_message.py)

data_structures/stacks/stack.py

@@ -1,4 +1,5 @@
-__author__ = "Omkar Pathak"
+class StackOverflowError(BaseException):
+    pass
 
 
 class Stack:
@@ -7,18 +8,17 @@ class Stack:
     element to the top of the stack, and pop() removes an element from the top
     of a stack. The order in which elements come off of a stack are
     Last In, First Out (LIFO).
-
     https://en.wikipedia.org/wiki/Stack_(abstract_data_type)
     """
 
-    def __init__(self, limit=10):
+    def __init__(self, limit: int = 10):
         self.stack = []
         self.limit = limit
 
-    def __bool__(self):
+    def __bool__(self) -> bool:
         return bool(self.stack)
 
-    def __str__(self):
+    def __str__(self) -> str:
         return str(self.stack)
 
     def push(self, data):
@@ -29,21 +29,20 @@ class Stack:
 
     def pop(self):
         """ Pop an element off of the top of the stack."""
-        if self.stack:
+        return self.stack.pop()
-            return self.stack.pop()
-        else:
-            raise IndexError("pop from an empty stack")
 
     def peek(self):
         """ Peek at the top-most element of the stack."""
-        if self.stack:
+        return self.stack[-1]
-            return self.stack[-1]
 
-    def is_empty(self):
+    def is_empty(self) -> bool:
         """ Check if a stack is empty."""
         return not bool(self.stack)
 
-    def size(self):
+    def is_full(self) -> bool:
+        return self.size() == self.limit
+
+    def size(self) -> int:
         """ Return the size of the stack."""
         return len(self.stack)
 
@@ -52,24 +51,54 @@ class Stack:
         return item in self.stack
 
 
-class StackOverflowError(BaseException):
+def test_stack() -> None:
-    pass
+    """
+    >>> test_stack()
+    """
+    stack = Stack(10)
+    assert bool(stack) is False
+    assert stack.is_empty() is True
+    assert stack.is_full() is False
+    assert str(stack) == "[]"
+
+    try:
+        _ = stack.pop()
+        assert False  # This should not happen
+    except IndexError:
+        assert True  # This should happen
+
+    try:
+        _ = stack.peek()
+        assert False  # This should not happen
+    except IndexError:
+        assert True  # This should happen
+
+    for i in range(10):
+        assert stack.size() == i
+        stack.push(i)
+
+    assert bool(stack) is True
+    assert stack.is_empty() is False
+    assert stack.is_full() is True
+    assert str(stack) == str(list(range(10)))
+    assert stack.pop() == 9
+    assert stack.peek() == 8
+
+    stack.push(100)
+    assert str(stack) == str([0, 1, 2, 3, 4, 5, 6, 7, 8, 100])
+
+    try:
+        stack.push(200)
+        assert False  # This should not happen
+    except StackOverflowError:
+        assert True  # This should happen
+
+    assert stack.is_empty() is False
+    assert stack.size() == 10
+
+    assert 5 in stack
+    assert 55 not in stack
 
 
 if __name__ == "__main__":
-    stack = Stack()
+    test_stack()
-    for i in range(10):
-        stack.push(i)
-
-    print("Stack demonstration:\n")
-    print("Initial stack: " + str(stack))
-    print("pop(): " + str(stack.pop()))
-    print("After pop(), the stack is now: " + str(stack))
-    print("peek(): " + str(stack.peek()))
-    stack.push(100)
-    print("After push(100), the stack is now: " + str(stack))
-    print("is_empty(): " + str(stack.is_empty()))
-    print("size(): " + str(stack.size()))
-    num = 5
-    if num in stack:
-        print(f"{num} is in stack")