Merge b632e4c72d06c75d872df8ff0f6540b7f395fae4 into 338cbafe0d5b07d57f83060ea0f9ba3a6c1155e7

* Fix And Add power.py

To fix the inaccuracies and allow handling of negative exponents and bases, the key issue lies in how negative numbers are handled in the power calculation, especially when dividing.
## Example Output:
```python
>>> power(4, 6)
4096
>>> power(2, 3)
8
>>> power(-2, 3)
-8
>>> power(2, -3)
0.125
>>> power(-2, -3)
-0.125
```

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update power.py

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update power.py

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update power.py

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update power.py

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Maxim Smolskiy <mithridatus@mail.ru>

.github/workflows/sphinx.yml

@@ -23,7 +23,7 @@ concurrency:
 
 jobs:
   build_docs:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04-arm
     steps:
       - uses: actions/checkout@v4
       - uses: astral-sh/setup-uv@v5

.pre-commit-config.yaml

@@ -16,13 +16,13 @@ repos:
       - id: auto-walrus
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.9.1
+    rev: v0.9.4
     hooks:
       - id: ruff
       - id: ruff-format
 
   - repo: https://github.com/codespell-project/codespell
-    rev: v2.3.0
+    rev: v2.4.1
     hooks:
       - id: codespell
         additional_dependencies:

DIRECTORY.md

@@ -377,6 +377,7 @@
   * [Longest Common Subsequence](dynamic_programming/longest_common_subsequence.py)
   * [Longest Common Substring](dynamic_programming/longest_common_substring.py)
   * [Longest Increasing Subsequence](dynamic_programming/longest_increasing_subsequence.py)
+  * [Longest Increasing Subsequence Iterative](dynamic_programming/longest_increasing_subsequence_iterative.py)
   * [Longest Increasing Subsequence O Nlogn](dynamic_programming/longest_increasing_subsequence_o_nlogn.py)
   * [Longest Palindromic Subsequence](dynamic_programming/longest_palindromic_subsequence.py)
   * [Matrix Chain Multiplication](dynamic_programming/matrix_chain_multiplication.py)
@@ -462,6 +463,7 @@
 
 ## Graphics
   * [Bezier Curve](graphics/bezier_curve.py)
+  * [Butterfly Pattern](graphics/butterfly_pattern.py)
   * [Digital Differential Analyzer Line](graphics/digital_differential_analyzer_line.py)
   * [Vector3 For 2D Rendering](graphics/vector3_for_2d_rendering.py)
 

ciphers/trifid_cipher.py

@@ -88,7 +88,7 @@ def __prepare(
         ...
     KeyError: 'Length of alphabet has to be 27.'
 
-    Testing with punctuations that are not in the given alphabet
+    Testing with punctuation not in the given alphabet
 
     >>> __prepare('am i a boy?','abCdeFghijkLmnopqrStuVwxYZ+')
     Traceback (most recent call last):
@@ -128,7 +128,7 @@ def encrypt_message(
     encrypt_message
     ===============
 
-    Encrypts a message using the trifid_cipher. Any punctuatuions that
+    Encrypts a message using the trifid_cipher. Any punctuatuion chars that
     would be used should be added to the alphabet.
 
     PARAMETERS

data_structures/arrays/sudoku_solver.py

@@ -9,7 +9,9 @@ import time
 
 
 def cross(items_a, items_b):
-    "Cross product of elements in A and elements in B."
+    """
+    Cross product of elements in A and elements in B.
+    """
     return [a + b for a in items_a for b in items_b]
 
 
@@ -27,7 +29,7 @@ peers = {s: {x for u in units[s] for x in u} - {s} for s in squares}
 
 
 def test():
-    "A set of unit tests."
+    """A set of unit tests."""
     assert len(squares) == 81
     assert len(unitlist) == 27
     assert all(len(units[s]) == 3 for s in squares)
@@ -47,8 +49,10 @@ def test():
 
 
 def parse_grid(grid):
-    """Convert grid to a dict of possible values, {square: digits}, or
-    return False if a contradiction is detected."""
+    """
+    Convert grid to a dict of possible values, {square: digits}, or
+    return False if a contradiction is detected.
+    """
     ## To start, every square can be any digit; then assign values from the grid.
     values = {s: digits for s in squares}
     for s, d in grid_values(grid).items():
@@ -58,15 +62,19 @@ def parse_grid(grid):
 
 
 def grid_values(grid):
-    "Convert grid into a dict of {square: char} with '0' or '.' for empties."
+    """
+    Convert grid into a dict of {square: char} with '0' or '.' for empties.
+    """
     chars = [c for c in grid if c in digits or c in "0."]
     assert len(chars) == 81
     return dict(zip(squares, chars))
 
 
 def assign(values, s, d):
-    """Eliminate all the other values (except d) from values[s] and propagate.
-    Return values, except return False if a contradiction is detected."""
+    """
+    Eliminate all the other values (except d) from values[s] and propagate.
+    Return values, except return False if a contradiction is detected.
+    """
     other_values = values[s].replace(d, "")
     if all(eliminate(values, s, d2) for d2 in other_values):
         return values
@@ -75,8 +83,10 @@ def assign(values, s, d):
 
 
 def eliminate(values, s, d):
-    """Eliminate d from values[s]; propagate when values or places <= 2.
-    Return values, except return False if a contradiction is detected."""
+    """
+    Eliminate d from values[s]; propagate when values or places <= 2.
+    Return values, except return False if a contradiction is detected.
+    """
     if d not in values[s]:
         return values  ## Already eliminated
     values[s] = values[s].replace(d, "")
@@ -99,7 +109,9 @@ def eliminate(values, s, d):
 
 
 def display(values):
-    "Display these values as a 2-D grid."
+    """
+    Display these values as a 2-D grid.
+    """
     width = 1 + max(len(values[s]) for s in squares)
     line = "+".join(["-" * (width * 3)] * 3)
     for r in rows:
@@ -114,11 +126,14 @@ def display(values):
 
 
 def solve(grid):
+    """
+    Solve the grid.
+    """
     return search(parse_grid(grid))
 
 
 def some(seq):
-    "Return some element of seq that is true."
+    """Return some element of seq that is true."""
     for e in seq:
         if e:
             return e
@@ -126,7 +141,9 @@ def some(seq):
 
 
 def search(values):
-    "Using depth-first search and propagation, try all possible values."
+    """
+    Using depth-first search and propagation, try all possible values.
+    """
     if values is False:
         return False  ## Failed earlier
     if all(len(values[s]) == 1 for s in squares):
@@ -137,9 +154,11 @@ def search(values):
 
 
 def solve_all(grids, name="", showif=0.0):
-    """Attempt to solve a sequence of grids. Report results.
+    """
+    Attempt to solve a sequence of grids. Report results.
     When showif is a number of seconds, display puzzles that take longer.
-    When showif is None, don't display any puzzles."""
+    When showif is None, don't display any puzzles.
+    """
 
     def time_solve(grid):
         start = time.monotonic()
@@ -162,7 +181,9 @@ def solve_all(grids, name="", showif=0.0):
 
 
 def solved(values):
-    "A puzzle is solved if each unit is a permutation of the digits 1 to 9."
+    """
+    A puzzle is solved if each unit is a permutation of the digits 1 to 9.
+    """
 
     def unitsolved(unit):
         return {values[s] for s in unit} == set(digits)
@@ -177,9 +198,11 @@ def from_file(filename, sep="\n"):
 
 
 def random_puzzle(assignments=17):
-    """Make a random puzzle with N or more assignments. Restart on contradictions.
+    """
+    Make a random puzzle with N or more assignments. Restart on contradictions.
     Note the resulting puzzle is not guaranteed to be solvable, but empirically
-    about 99.8% of them are solvable. Some have multiple solutions."""
+    about 99.8% of them are solvable. Some have multiple solutions.
+    """
     values = {s: digits for s in squares}
     for s in shuffled(squares):
         if not assign(values, s, random.choice(values[s])):
@@ -191,7 +214,9 @@ def random_puzzle(assignments=17):
 
 
 def shuffled(seq):
-    "Return a randomly shuffled copy of the input sequence."
+    """
+    Return a randomly shuffled copy of the input sequence.
+    """
     seq = list(seq)
     random.shuffle(seq)
     return seq

data_structures/binary_tree/avl_tree.py

@@ -221,6 +221,10 @@ def del_node(root: MyNode, data: Any) -> MyNode | None:
     else:
         root.set_right(del_node(right_child, data))
 
+    # Re-fetch left_child and right_child references
+    left_child = root.get_left()
+    right_child = root.get_right()
+
     if get_height(right_child) - get_height(left_child) == 2:
         assert right_child is not None
         if get_height(right_child.get_right()) > get_height(right_child.get_left()):

divide_and_conquer/power.py

@@ -1,4 +1,4 @@
-def actual_power(a: int, b: int):
+def actual_power(a: int, b: int) -> int:
     """
     Function using divide and conquer to calculate a^b.
     It only works for integer a,b.
@@ -19,10 +19,12 @@ def actual_power(a: int, b: int):
     """
     if b == 0:
         return 1
+    half = actual_power(a, b // 2)
+
     if (b % 2) == 0:
-        return actual_power(a, int(b / 2)) * actual_power(a, int(b / 2))
+        return half * half
     else:
-        return a * actual_power(a, int(b / 2)) * actual_power(a, int(b / 2))
+        return a * half * half
 
 
 def power(a: int, b: int) -> float:
@@ -43,9 +45,9 @@ def power(a: int, b: int) -> float:
     -0.125
     """
     if b < 0:
-        return 1 / actual_power(a, b)
+        return 1 / actual_power(a, -b)
     return actual_power(a, b)
 
 
 if __name__ == "__main__":
-    print(power(-2, -3))
+    print(power(-2, -3))  # output -0.125

dynamic_programming/longest_increasing_subsequence_iterative.py

@@ -0,0 +1,72 @@
+"""
+Author  : Sanjay Muthu <https://github.com/XenoBytesX>
+
+This is a pure Python implementation of Dynamic Programming solution to the longest
+increasing subsequence of a given sequence.
+
+The problem is:
+    Given an array, to find the longest and increasing sub-array in that given array and
+    return it.
+
+Example:
+    ``[10, 22, 9, 33, 21, 50, 41, 60, 80]`` as input will return
+    ``[10, 22, 33, 50, 60, 80]`` as output
+"""
+
+from __future__ import annotations
+
+import copy
+
+
+def longest_subsequence(array: list[int]) -> list[int]:
+    """
+    Some examples
+
+    >>> longest_subsequence([10, 22, 9, 33, 21, 50, 41, 60, 80])
+    [10, 22, 33, 50, 60, 80]
+    >>> longest_subsequence([4, 8, 7, 5, 1, 12, 2, 3, 9])
+    [1, 2, 3, 9]
+    >>> longest_subsequence([9, 8, 7, 6, 5, 7])
+    [7, 7]
+    >>> longest_subsequence([28, 26, 12, 23, 35, 39])
+    [12, 23, 35, 39]
+    >>> longest_subsequence([1, 1, 1])
+    [1, 1, 1]
+    >>> longest_subsequence([])
+    []
+    """
+    n = len(array)
+    # The longest increasing subsequence ending at array[i]
+    longest_increasing_subsequence = []
+    for i in range(n):
+        longest_increasing_subsequence.append([array[i]])
+
+    for i in range(1, n):
+        for prev in range(i):
+            # If array[prev] is less than or equal to array[i], then
+            # longest_increasing_subsequence[prev] + array[i]
+            # is a valid increasing subsequence
+
+            # longest_increasing_subsequence[i] is only set to
+            # longest_increasing_subsequence[prev] + array[i] if the length is longer.
+
+            if array[prev] <= array[i] and len(
+                longest_increasing_subsequence[prev]
+            ) + 1 > len(longest_increasing_subsequence[i]):
+                longest_increasing_subsequence[i] = copy.copy(
+                    longest_increasing_subsequence[prev]
+                )
+                longest_increasing_subsequence[i].append(array[i])
+
+    result: list[int] = []
+    for i in range(n):
+        if len(longest_increasing_subsequence[i]) > len(result):
+            result = longest_increasing_subsequence[i]
+
+    return result
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()

graphics/butterfly_pattern.py

@@ -0,0 +1,46 @@
+def butterfly_pattern(n: int) -> str:
+    """
+    Creates a butterfly pattern of size n and returns it as a string.
+
+    >>> print(butterfly_pattern(3))
+    *   *
+    ** **
+    *****
+    ** **
+    *   *
+    >>> print(butterfly_pattern(5))
+    *       *
+    **     **
+    ***   ***
+    **** ****
+    *********
+    **** ****
+    ***   ***
+    **     **
+    *       *
+    """
+    result = []
+
+    # Upper part
+    for i in range(1, n):
+        left_stars = "*" * i
+        spaces = " " * (2 * (n - i) - 1)
+        right_stars = "*" * i
+        result.append(left_stars + spaces + right_stars)
+
+    # Middle part
+    result.append("*" * (2 * n - 1))
+
+    # Lower part
+    for i in range(n - 1, 0, -1):
+        left_stars = "*" * i
+        spaces = " " * (2 * (n - i) - 1)
+        right_stars = "*" * i
+        result.append(left_stars + spaces + right_stars)
+
+    return "\n".join(result)
+
+
+if __name__ == "__main__":
+    n = int(input("Enter the size of the butterfly pattern: "))
+    print(butterfly_pattern(n))

other/doomsday.py

@@ -46,7 +46,7 @@ def get_week_day(year: int, month: int, day: int) -> str:
     ) % 7
     day_anchor = (
         DOOMSDAY_NOT_LEAP[month - 1]
-        if (year % 4 != 0) or (centurian == 0 and (year % 400) == 0)
+        if year % 4 != 0 or (centurian == 0 and year % 400 != 0)
         else DOOMSDAY_LEAP[month - 1]
     )
     week_day = (dooms_day + day - day_anchor) % 7

pyproject.toml

@@ -159,7 +159,7 @@ lint.pylint.max-returns = 8 # default: 6
 lint.pylint.max-statements = 88 # default: 50
 
 [tool.codespell]
-ignore-words-list = "3rt,ans,bitap,crate,damon,fo,followings,hist,iff,kwanza,manuel,mater,secant,som,sur,tim,toi,zar"
+ignore-words-list = "3rt,abd,aer,ans,bitap,crate,damon,fo,followings,hist,iff,kwanza,manuel,mater,secant,som,sur,tim,toi,zar"
 skip = "./.*,*.json,*.lock,ciphers/prehistoric_men.txt,project_euler/problem_022/p022_names.txt,pyproject.toml,strings/dictionary.txt,strings/words.txt"
 
 [tool.pytest.ini_options]

sorts/bubble_sort.py

@@ -85,6 +85,8 @@ def bubble_sort_recursive(collection: list[Any]) -> list[Any]:
     [1.1, 2.2, 3.3, 4.4, 5.5, 6.6, 7.7]
     >>> bubble_sort_recursive([1, 3.3, 5, 7.7, 2, 4.4, 6])
     [1, 2, 3.3, 4.4, 5, 6, 7.7]
+    >>> bubble_sort_recursive(['a', 'Z', 'B', 'C', 'A', 'c'])
+    ['A', 'B', 'C', 'Z', 'a', 'c']
     >>> import random
     >>> collection_arg = random.sample(range(-50, 50), 100)
     >>> bubble_sort_recursive(collection_arg) == sorted(collection_arg)

strings/suffix_automaton.py

@@ -0,0 +1,150 @@
+from __future__ import annotations
+
+
+class SuffixAutomaton:
+    """
+    Suffix Automaton data structure for efficient substring counting and searching.
+
+    Usage:
+    sa = SuffixAutomaton()
+    sa.extend('abc')
+    terminal_states = sa.terminal()
+    is_found = sa.find('ab')
+
+    :param alpha: Number of characters in the alphabet
+    (default is 26 for lowercase English letters)
+    :param first: ASCII value of the first character in the alphabet (default is 'a')
+    """
+
+    def __init__(self, alpha: int = 26, first: int = ord("a")):
+        self.alpha = alpha
+        self.first = first
+        self.substrings = 0
+        self.last = 0
+        self.st = [self.Node(0, -1, [0] * self.alpha)]
+
+    class Node:
+        def __init__(self, length: int, link: int, next_states: list[int]):
+            self.len = length
+            self.link = link
+            self.next = next_states
+
+    def extend(self, c: str) -> None:
+        """
+        Extend the suffix automaton with a new character.
+
+        :param c: The character to extend with.
+
+        >>> sa = SuffixAutomaton()
+        >>> sa.add('aabaaab')
+        >>> terminal_states = [7, 3, 0]
+        >>> sa.terminal() == terminal_states
+        True
+        >>> sa.find('a')
+        True
+        >>> sa.find('b')
+        True
+        >>> sa.find('c')
+        False
+        >>> sa.find('aa')
+        True
+        >>> sa.find('ab')
+        True
+        >>> sa.find('aaaab')
+        False
+        >>> sa.find('bab')
+        False
+        >>> sa.find('baaaab')
+        False
+        >>> sa.find('baaaaab')
+        False
+        >>> sa.extend('xy')  # doctest: +IGNORE_EXCEPTION_DETAIL
+        Traceback (most recent call last):
+            ...
+        ValueError: Invalid input to extend method. Only single characters are allowed.
+        """
+        if len(c) != 1:
+            raise ValueError("The character to extend with must be a single character.")
+
+        char_value = ord(c) - self.first
+        cur = len(self.st)
+        p, q = self.last, 0
+
+        self.st.append(self.Node(self.st[p].len + 1, -1, [0] * self.alpha))
+
+        while p != -1 and not self.st[p].next[char_value]:
+            self.st[p].next[char_value] = cur
+            p = self.st[p].link
+
+        if p == -1:
+            self.st[cur].link = 0
+            self.substrings += self.st[cur].len
+        else:
+            q = self.st[p].next[char_value]
+
+            if self.st[p].len + 1 == self.st[q].len:
+                self.st[cur].link = q
+                self.substrings += self.st[cur].len - self.st[q].len
+            else:
+                clone = len(self.st)
+                self.st.append(
+                    self.Node(self.st[p].len + 1, self.st[q].link, self.st[q].next[:])
+                )
+                self.substrings += self.st[clone].len - self.st[self.st[clone].link].len
+
+                while p != -1 and self.st[p].next[char_value] == q:
+                    self.st[p].next[char_value] = clone
+                    p = self.st[p].link
+
+                self.substrings -= self.st[q].len - self.st[self.st[q].link].len
+                self.st[q].link = self.st[cur].link = clone
+                self.substrings += (
+                    self.st[q].len
+                    - self.st[self.st[q].link].len
+                    + self.st[cur].len
+                    - self.st[self.st[cur].link].len
+                )
+
+        self.last = cur
+
+    def add(self, s: str) -> None:
+        """
+        Add a string to the suffix automaton.
+
+        :param s: The string to add.
+        """
+        for i in range(len(s)):
+            self.extend(s[i])
+
+    def terminal(self) -> list[int]:
+        """
+        Get the terminal states of the suffix automaton.
+
+        :return: List of terminal states.
+        """
+        p = self.last
+        terminal_states = []
+        while p >= 0:
+            terminal_states.append(p)
+            p = self.st[p].link
+        return terminal_states
+
+    def find(self, s: str) -> bool:
+        """
+        Check if a string is present in the suffix automaton.
+
+        :param s: The string to search for.
+        :return: True if the string is found, False otherwise.
+        """
+        p = 0
+        for j in range(len(s)):
+            if not self.st[p].next[ord(s[j]) - self.first]:
+                return False
+            p = self.st[p].next[ord(s[j]) - self.first]
+        return True
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()