Merge branch 'TheAlgorithms:master' into master

Author: codec4

.pre-commit-config.yaml

@@ -16,7 +16,7 @@ repos:
       - id: auto-walrus
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.8.6
+    rev: v0.9.1
     hooks:
       - id: ruff
       - id: ruff-format

DIRECTORY.md

@@ -86,7 +86,7 @@
   * [Baconian Cipher](ciphers/baconian_cipher.py)
   * [Base16](ciphers/base16.py)
   * [Base32](ciphers/base32.py)
-  * [Base64](ciphers/base64.py)
+  * [Base64 Cipher](ciphers/base64_cipher.py)
   * [Base85](ciphers/base85.py)
   * [Beaufort Cipher](ciphers/beaufort_cipher.py)
   * [Bifid](ciphers/bifid.py)
@@ -1331,7 +1331,7 @@
   * [Title](strings/title.py)
   * [Top K Frequent Words](strings/top_k_frequent_words.py)
   * [Upper](strings/upper.py)
-  * [Wave](strings/wave.py)
+  * [Wave String](strings/wave_string.py)
   * [Wildcard Pattern Matching](strings/wildcard_pattern_matching.py)
   * [Word Occurrence](strings/word_occurrence.py)
   * [Word Patterns](strings/word_patterns.py)

backtracking/all_combinations.py

@@ -12,6 +12,8 @@
 
 def combination_lists(n: int, k: int) -> list[list[int]]:
     """
+    Generates all possible combinations of k numbers out of 1 ... n using itertools.
+
     >>> combination_lists(n=4, k=2)
     [[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]]
     """
@@ -20,6 +22,8 @@ def combination_lists(n: int, k: int) -> list[list[int]]:
 
 def generate_all_combinations(n: int, k: int) -> list[list[int]]:
     """
+    Generates all possible combinations of k numbers out of 1 ... n using backtracking.
+
     >>> generate_all_combinations(n=4, k=2)
     [[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]]
     >>> generate_all_combinations(n=0, k=0)
@@ -34,6 +38,14 @@ def generate_all_combinations(n: int, k: int) -> list[list[int]]:
     ValueError: n must not be negative
     >>> generate_all_combinations(n=5, k=4)
     [[1, 2, 3, 4], [1, 2, 3, 5], [1, 2, 4, 5], [1, 3, 4, 5], [2, 3, 4, 5]]
+    >>> generate_all_combinations(n=3, k=3)
+    [[1, 2, 3]]
+    >>> generate_all_combinations(n=3, k=1)
+    [[1], [2], [3]]
+    >>> generate_all_combinations(n=1, k=0)
+    [[]]
+    >>> generate_all_combinations(n=1, k=1)
+    [[1]]
     >>> from itertools import combinations
     >>> all(generate_all_combinations(n, k) == combination_lists(n, k)
     ...     for n in range(1, 6) for k in range(1, 6))
@@ -56,6 +68,28 @@ def create_all_state(
     current_list: list[int],
     total_list: list[list[int]],
 ) -> None:
+    """
+    Helper function to recursively build all combinations.
+
+    >>> create_all_state(1, 4, 2, [], result := [])
+    >>> result
+    [[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]]
+    >>> create_all_state(1, 3, 3, [], result := [])
+    >>> result
+    [[1, 2, 3]]
+    >>> create_all_state(2, 2, 1, [1], result := [])
+    >>> result
+    [[1, 2]]
+    >>> create_all_state(1, 0, 0, [], result := [])
+    >>> result
+    [[]]
+    >>> create_all_state(1, 4, 0, [1, 2], result := [])
+    >>> result
+    [[1, 2]]
+    >>> create_all_state(5, 4, 2, [1, 2], result := [])
+    >>> result
+    []
+    """
     if level == 0:
         total_list.append(current_list[:])
         return

ciphers/base64.py renamed to ciphers/base64_cipher.py

@@ -105,13 +105,13 @@ def base64_decode(encoded_data: str) -> bytes:
 
     # Check if the encoded string contains non base64 characters
     if padding:
-        assert all(
-            char in B64_CHARSET for char in encoded_data[:-padding]
-        ), "Invalid base64 character(s) found."
+        assert all(char in B64_CHARSET for char in encoded_data[:-padding]), (
+            "Invalid base64 character(s) found."
+        )
     else:
-        assert all(
-            char in B64_CHARSET for char in encoded_data
-        ), "Invalid base64 character(s) found."
+        assert all(char in B64_CHARSET for char in encoded_data), (
+            "Invalid base64 character(s) found."
+        )
 
     # Check the padding
     assert len(encoded_data) % 4 == 0 and padding < 3, "Incorrect padding"

ciphers/caesar_cipher.py

@@ -225,7 +225,7 @@ def brute_force(input_string: str, alphabet: str | None = None) -> dict[int, str
 
 if __name__ == "__main__":
     while True:
-        print(f'\n{"-" * 10}\n Menu\n{"-" * 10}')
+        print(f"\n{'-' * 10}\n Menu\n{'-' * 10}")
         print(*["1.Encrypt", "2.Decrypt", "3.BruteForce", "4.Quit"], sep="\n")
 
         # get user input

computer_vision/flip_augmentation.py

@@ -33,7 +33,7 @@ def main() -> None:
         file_name = paths[index].split(os.sep)[-1].rsplit(".", 1)[0]
         file_root = f"{OUTPUT_DIR}/{file_name}_FLIP_{letter_code}"
         cv2.imwrite(f"{file_root}.jpg", image, [cv2.IMWRITE_JPEG_QUALITY, 85])
-        print(f"Success {index+1}/{len(new_images)} with {file_name}")
+        print(f"Success {index + 1}/{len(new_images)} with {file_name}")
         annos_list = []
         for anno in new_annos[index]:
             obj = f"{anno[0]} {anno[1]} {anno[2]} {anno[3]} {anno[4]}"

computer_vision/mosaic_augmentation.py

@@ -41,7 +41,7 @@ def main() -> None:
         file_name = path.split(os.sep)[-1].rsplit(".", 1)[0]
         file_root = f"{OUTPUT_DIR}/{file_name}_MOSAIC_{letter_code}"
         cv2.imwrite(f"{file_root}.jpg", new_image, [cv2.IMWRITE_JPEG_QUALITY, 85])
-        print(f"Succeeded {index+1}/{NUMBER_IMAGES} with {file_name}")
+        print(f"Succeeded {index + 1}/{NUMBER_IMAGES} with {file_name}")
         annos_list = []
         for anno in new_annos:
             width = anno[3] - anno[1]

data_structures/hashing/number_theory/prime_numbers.py

@@ -32,9 +32,9 @@ def is_prime(number: int) -> bool:
     """
 
     # precondition
-    assert isinstance(number, int) and (
-        number >= 0
-    ), "'number' must been an int and positive"
+    assert isinstance(number, int) and (number >= 0), (
+        "'number' must been an int and positive"
+    )
 
     if 1 < number < 4:
         # 2 and 3 are primes

data_structures/heap/min_heap.py

@@ -124,9 +124,9 @@ def is_empty(self):
         return len(self.heap) == 0
 
     def decrease_key(self, node, new_value):
-        assert (
-            self.heap[self.idx_of_element[node]].val > new_value
-        ), "newValue must be less that current value"
+        assert self.heap[self.idx_of_element[node]].val > new_value, (
+            "newValue must be less that current value"
+        )
         node.val = new_value
         self.heap_dict[node.name] = new_value
         self.sift_up(self.idx_of_element[node])

data_structures/kd_tree/tests/test_kdtree.py

@@ -48,14 +48,14 @@ def test_build_kdtree(num_points, cube_size, num_dimensions, depth, expected_res
         assert kdtree is not None, "Expected a KDNode, got None"
 
         # Check if root has correct dimensions
-        assert (
-            len(kdtree.point) == num_dimensions
-        ), f"Expected point dimension {num_dimensions}, got {len(kdtree.point)}"
+        assert len(kdtree.point) == num_dimensions, (
+            f"Expected point dimension {num_dimensions}, got {len(kdtree.point)}"
+        )
 
         # Check that the tree is balanced to some extent (simplistic check)
-        assert isinstance(
-            kdtree, KDNode
-        ), f"Expected KDNode instance, got {type(kdtree)}"
+        assert isinstance(kdtree, KDNode), (
+            f"Expected KDNode instance, got {type(kdtree)}"
+        )
 
 
 def test_nearest_neighbour_search():

data_structures/suffix_tree/tests/test_suffix_tree.py

@@ -22,37 +22,37 @@ def test_search_existing_patterns(self) -> None:
         patterns = ["ana", "ban", "na"]
         for pattern in patterns:
             with self.subTest(pattern=pattern):
-                assert self.suffix_tree.search(
-                    pattern
-                ), f"Pattern '{pattern}' should be found."
+                assert self.suffix_tree.search(pattern), (
+                    f"Pattern '{pattern}' should be found."
+                )
 
     def test_search_non_existing_patterns(self) -> None:
         """Test searching for patterns that do not exist in the suffix tree."""
         patterns = ["xyz", "apple", "cat"]
         for pattern in patterns:
             with self.subTest(pattern=pattern):
-                assert not self.suffix_tree.search(
-                    pattern
-                ), f"Pattern '{pattern}' should not be found."
+                assert not self.suffix_tree.search(pattern), (
+                    f"Pattern '{pattern}' should not be found."
+                )
 
     def test_search_empty_pattern(self) -> None:
         """Test searching for an empty pattern."""
         assert self.suffix_tree.search(""), "An empty pattern should be found."
 
     def test_search_full_text(self) -> None:
         """Test searching for the full text."""
-        assert self.suffix_tree.search(
-            self.text
-        ), "The full text should be found in the suffix tree."
+        assert self.suffix_tree.search(self.text), (
+            "The full text should be found in the suffix tree."
+        )
 
     def test_search_substrings(self) -> None:
         """Test searching for substrings of the full text."""
         substrings = ["ban", "ana", "a", "na"]
         for substring in substrings:
             with self.subTest(substring=substring):
-                assert self.suffix_tree.search(
-                    substring
-                ), f"Substring '{substring}' should be found."
+                assert self.suffix_tree.search(substring), (
+                    f"Substring '{substring}' should be found."
+                )
 
 
 if __name__ == "__main__":

dynamic_programming/climbing_stairs.py

@@ -25,9 +25,9 @@ def climb_stairs(number_of_steps: int) -> int:
         ...
     AssertionError: number_of_steps needs to be positive integer, your input -7
     """
-    assert (
-        isinstance(number_of_steps, int) and number_of_steps > 0
-    ), f"number_of_steps needs to be positive integer, your input {number_of_steps}"
+    assert isinstance(number_of_steps, int) and number_of_steps > 0, (
+        f"number_of_steps needs to be positive integer, your input {number_of_steps}"
+    )
     if number_of_steps == 1:
         return 1
     previous, current = 1, 1

dynamic_programming/iterating_through_submasks.py

@@ -37,9 +37,9 @@ def list_of_submasks(mask: int) -> list[int]:
 
     """
 
-    assert (
-        isinstance(mask, int) and mask > 0
-    ), f"mask needs to be positive integer, your input {mask}"
+    assert isinstance(mask, int) and mask > 0, (
+        f"mask needs to be positive integer, your input {mask}"
+    )
 
     """
     first submask iterated will be mask itself then operation will be performed

dynamic_programming/longest_increasing_subsequence.py

@@ -24,8 +24,10 @@ def longest_subsequence(array: list[int]) -> list[int]:  # This function is recu
     [10, 22, 33, 41, 60, 80]
     >>> longest_subsequence([4, 8, 7, 5, 1, 12, 2, 3, 9])
     [1, 2, 3, 9]
+    >>> longest_subsequence([28, 26, 12, 23, 35, 39])
+    [12, 23, 35, 39]
     >>> longest_subsequence([9, 8, 7, 6, 5, 7])
-    [8]
+    [5, 7]
     >>> longest_subsequence([1, 1, 1])
     [1, 1, 1]
     >>> longest_subsequence([])
@@ -44,7 +46,7 @@ def longest_subsequence(array: list[int]) -> list[int]:  # This function is recu
     while not is_found and i < array_length:
         if array[i] < pivot:
             is_found = True
-            temp_array = [element for element in array[i:] if element >= array[i]]
+            temp_array = array[i:]
             temp_array = longest_subsequence(temp_array)
             if len(temp_array) > len(longest_subseq):
                 longest_subseq = temp_array

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()

dynamic_programming/matrix_chain_multiplication.py

@@ -134,7 +134,7 @@ def elapsed_time(msg: str) -> Iterator:
 
     start = perf_counter_ns()
     yield
-    print(f"Finished: {msg} in {(perf_counter_ns() - start) / 10 ** 9} seconds.")
+    print(f"Finished: {msg} in {(perf_counter_ns() - start) / 10**9} seconds.")
 
 
 if __name__ == "__main__":