Travis CI: Start testing on Python 3.9 beta 5

.travis.yml

@@ -1,7 +1,7 @@
 os: linux
 dist: focal
 language: python
-python: 3.8
+python: "3.9-dev"
 cache: pip
 before_install: pip install --upgrade pip setuptools six
 install: pip install black flake8

DIRECTORY.md

@@ -85,7 +85,9 @@
   * [Decimal To Binary](https://github.com/TheAlgorithms/Python/blob/master/conversions/decimal_to_binary.py)
   * [Decimal To Hexadecimal](https://github.com/TheAlgorithms/Python/blob/master/conversions/decimal_to_hexadecimal.py)
   * [Decimal To Octal](https://github.com/TheAlgorithms/Python/blob/master/conversions/decimal_to_octal.py)
+  * [Prefix Conversions](https://github.com/TheAlgorithms/Python/blob/master/conversions/prefix_conversions.py)
   * [Roman To Integer](https://github.com/TheAlgorithms/Python/blob/master/conversions/roman_to_integer.py)
+  * [Temperature Conversions](https://github.com/TheAlgorithms/Python/blob/master/conversions/temperature_conversions.py)
 
 ## Data Structures
   * Binary Tree
@@ -102,9 +104,6 @@
     * [Segment Tree](https://github.com/TheAlgorithms/Python/blob/master/data_structures/binary_tree/segment_tree.py)
     * [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)
-  * Data Structures
-    * Heap
-      * [Heap Generic](https://github.com/TheAlgorithms/Python/blob/master/data_structures/data_structures/heap/heap_generic.py)
   * Disjoint Set
     * [Disjoint Set](https://github.com/TheAlgorithms/Python/blob/master/data_structures/disjoint_set/disjoint_set.py)
   * Hashing
@@ -117,6 +116,7 @@
   * Heap
     * [Binomial Heap](https://github.com/TheAlgorithms/Python/blob/master/data_structures/heap/binomial_heap.py)
     * [Heap](https://github.com/TheAlgorithms/Python/blob/master/data_structures/heap/heap.py)
+    * [Heap Generic](https://github.com/TheAlgorithms/Python/blob/master/data_structures/heap/heap_generic.py)
     * [Max Heap](https://github.com/TheAlgorithms/Python/blob/master/data_structures/heap/max_heap.py)
     * [Min Heap](https://github.com/TheAlgorithms/Python/blob/master/data_structures/heap/min_heap.py)
   * Linked List
@@ -264,6 +264,7 @@
   * [Greedy Best First](https://github.com/TheAlgorithms/Python/blob/master/graphs/greedy_best_first.py)
   * [Kahns Algorithm Long](https://github.com/TheAlgorithms/Python/blob/master/graphs/kahns_algorithm_long.py)
   * [Kahns Algorithm Topo](https://github.com/TheAlgorithms/Python/blob/master/graphs/kahns_algorithm_topo.py)
+  * [Karger](https://github.com/TheAlgorithms/Python/blob/master/graphs/karger.py)
   * [Minimum Spanning Tree Boruvka](https://github.com/TheAlgorithms/Python/blob/master/graphs/minimum_spanning_tree_boruvka.py)
   * [Minimum Spanning Tree Kruskal](https://github.com/TheAlgorithms/Python/blob/master/graphs/minimum_spanning_tree_kruskal.py)
   * [Minimum Spanning Tree Prims](https://github.com/TheAlgorithms/Python/blob/master/graphs/minimum_spanning_tree_prims.py)
@@ -292,6 +293,7 @@
   * Src
     * [Lib](https://github.com/TheAlgorithms/Python/blob/master/linear_algebra/src/lib.py)
     * [Polynom-For-Points](https://github.com/TheAlgorithms/Python/blob/master/linear_algebra/src/polynom-for-points.py)
+    * [Power Iteration](https://github.com/TheAlgorithms/Python/blob/master/linear_algebra/src/power_iteration.py)
     * [Rayleigh Quotient](https://github.com/TheAlgorithms/Python/blob/master/linear_algebra/src/rayleigh_quotient.py)
     * [Test Linear Algebra](https://github.com/TheAlgorithms/Python/blob/master/linear_algebra/src/test_linear_algebra.py)
 
@@ -337,6 +339,7 @@
   * [Binary Exp Mod](https://github.com/TheAlgorithms/Python/blob/master/maths/binary_exp_mod.py)
   * [Binary Exponentiation](https://github.com/TheAlgorithms/Python/blob/master/maths/binary_exponentiation.py)
   * [Binomial Coefficient](https://github.com/TheAlgorithms/Python/blob/master/maths/binomial_coefficient.py)
+  * [Binomial Distribution](https://github.com/TheAlgorithms/Python/blob/master/maths/binomial_distribution.py)
   * [Bisection](https://github.com/TheAlgorithms/Python/blob/master/maths/bisection.py)
   * [Ceil](https://github.com/TheAlgorithms/Python/blob/master/maths/ceil.py)
   * [Chudnovsky Algorithm](https://github.com/TheAlgorithms/Python/blob/master/maths/chudnovsky_algorithm.py)
@@ -366,6 +369,7 @@
   * [Jaccard Similarity](https://github.com/TheAlgorithms/Python/blob/master/maths/jaccard_similarity.py)
   * [Kadanes](https://github.com/TheAlgorithms/Python/blob/master/maths/kadanes.py)
   * [Karatsuba](https://github.com/TheAlgorithms/Python/blob/master/maths/karatsuba.py)
+  * [Krishnamurthy Number](https://github.com/TheAlgorithms/Python/blob/master/maths/krishnamurthy_number.py)
   * [Kth Lexicographic Permutation](https://github.com/TheAlgorithms/Python/blob/master/maths/kth_lexicographic_permutation.py)
   * [Largest Of Very Large Numbers](https://github.com/TheAlgorithms/Python/blob/master/maths/largest_of_very_large_numbers.py)
   * [Least Common Multiple](https://github.com/TheAlgorithms/Python/blob/master/maths/least_common_multiple.py)
@@ -382,9 +386,11 @@
   * [Number Of Digits](https://github.com/TheAlgorithms/Python/blob/master/maths/number_of_digits.py)
   * [Numerical Integration](https://github.com/TheAlgorithms/Python/blob/master/maths/numerical_integration.py)
   * [Perfect Cube](https://github.com/TheAlgorithms/Python/blob/master/maths/perfect_cube.py)
+  * [Perfect Number](https://github.com/TheAlgorithms/Python/blob/master/maths/perfect_number.py)
   * [Perfect Square](https://github.com/TheAlgorithms/Python/blob/master/maths/perfect_square.py)
   * [Pi Monte Carlo Estimation](https://github.com/TheAlgorithms/Python/blob/master/maths/pi_monte_carlo_estimation.py)
   * [Polynomial Evaluation](https://github.com/TheAlgorithms/Python/blob/master/maths/polynomial_evaluation.py)
+  * [Power Using Recursion](https://github.com/TheAlgorithms/Python/blob/master/maths/power_using_recursion.py)
   * [Prime Check](https://github.com/TheAlgorithms/Python/blob/master/maths/prime_check.py)
   * [Prime Factors](https://github.com/TheAlgorithms/Python/blob/master/maths/prime_factors.py)
   * [Prime Numbers](https://github.com/TheAlgorithms/Python/blob/master/maths/prime_numbers.py)
@@ -415,6 +421,7 @@
 
 ## Matrix
   * [Count Islands In Matrix](https://github.com/TheAlgorithms/Python/blob/master/matrix/count_islands_in_matrix.py)
+  * [Inverse Of Matrix](https://github.com/TheAlgorithms/Python/blob/master/matrix/inverse_of_matrix.py)
   * [Matrix Class](https://github.com/TheAlgorithms/Python/blob/master/matrix/matrix_class.py)
   * [Matrix Operation](https://github.com/TheAlgorithms/Python/blob/master/matrix/matrix_operation.py)
   * [Nth Fibonacci Using Matrix Exponentiation](https://github.com/TheAlgorithms/Python/blob/master/matrix/nth_fibonacci_using_matrix_exponentiation.py)
@@ -460,6 +467,7 @@
   * [Palindrome](https://github.com/TheAlgorithms/Python/blob/master/other/palindrome.py)
   * [Password Generator](https://github.com/TheAlgorithms/Python/blob/master/other/password_generator.py)
   * [Primelib](https://github.com/TheAlgorithms/Python/blob/master/other/primelib.py)
+  * [Scoring Algorithm](https://github.com/TheAlgorithms/Python/blob/master/other/scoring_algorithm.py)
   * [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)
@@ -633,6 +641,7 @@
   * [I Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/i_sort.py)
   * [Insertion Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/insertion_sort.py)
   * [Iterative Merge Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/iterative_merge_sort.py)
+  * [Merge Insertion Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/merge_insertion_sort.py)
   * [Merge Sort](https://github.com/TheAlgorithms/Python/blob/master/sorts/merge_sort.py)
   * [Odd Even Transposition Parallel](https://github.com/TheAlgorithms/Python/blob/master/sorts/odd_even_transposition_parallel.py)
   * [Odd Even Transposition Single Threaded](https://github.com/TheAlgorithms/Python/blob/master/sorts/odd_even_transposition_single_threaded.py)
@@ -693,3 +702,4 @@
   * [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)
+  * [World Covid19 Stats](https://github.com/TheAlgorithms/Python/blob/master/web_programming/world_covid19_stats.py)

arithmetic_analysis/newton_method.py

@@ -7,7 +7,11 @@
 
 
 # function is the f(x) and derivative is the f'(x)
-def newton(function: RealFunc, derivative: RealFunc, starting_int: int,) -> float:
+def newton(
+    function: RealFunc,
+    derivative: RealFunc,
+    starting_int: int,
+) -> float:
     """
     >>> newton(lambda x: x ** 3 - 2 * x - 5, lambda x: 3 * x ** 2 - 2, 3)
     2.0945514815423474

arithmetic_analysis/newton_raphson.py

@@ -9,7 +9,7 @@
 
 
 def newton_raphson(func: str, a: int, precision: int = 10 ** -10) -> float:
-    """ Finds root from the point 'a' onwards by Newton-Raphson method
+    """Finds root from the point 'a' onwards by Newton-Raphson method
     >>> newton_raphson("sin(x)", 2)
     3.1415926536808043
     >>> newton_raphson("x**2 - 5*x +2", 0.4)

backtracking/all_permutations.py

@@ -13,10 +13,10 @@ def generate_all_permutations(sequence):
 
 def create_state_space_tree(sequence, current_sequence, index, index_used):
     """
-        Creates a state space tree to iterate through each branch using DFS.
-        We know that each state has exactly len(sequence) - index children.
-        It terminates when it reaches the end of the given sequence.
-        """
+    Creates a state space tree to iterate through each branch using DFS.
+    We know that each state has exactly len(sequence) - index children.
+    It terminates when it reaches the end of the given sequence.
+    """
 
     if index == len(sequence):
         print(current_sequence)

backtracking/all_subsequences.py

@@ -13,10 +13,10 @@ def generate_all_subsequences(sequence):
 
 def create_state_space_tree(sequence, current_subsequence, index):
     """
-        Creates a state space tree to iterate through each branch using DFS.
-        We know that each state has exactly two children.
-        It terminates when it reaches the end of the given sequence.
-        """
+    Creates a state space tree to iterate through each branch using DFS.
+    We know that each state has exactly two children.
+    It terminates when it reaches the end of the given sequence.
+    """
 
     if index == len(sequence):
         print(current_subsequence)

backtracking/sudoku.py

@@ -105,7 +105,7 @@ def sudoku(grid):
      [7, 4, 5, 2, 8, 6, 3, 1, 9]]
      >>> sudoku(no_solution)
      False
-     """
+    """
 
     if is_completed(grid):
         return grid

backtracking/sum_of_subsets.py

@@ -19,13 +19,13 @@ def generate_sum_of_subsets_soln(nums, max_sum):
 
 def create_state_space_tree(nums, max_sum, num_index, path, result, remaining_nums_sum):
     """
-        Creates a state space tree to iterate through each branch using DFS.
-        It terminates the branching of a node when any of the two conditions
-        given below satisfy.
-        This algorithm follows depth-fist-search and backtracks when the node is not
-        branchable.
+    Creates a state space tree to iterate through each branch using DFS.
+    It terminates the branching of a node when any of the two conditions
+    given below satisfy.
+    This algorithm follows depth-fist-search and backtracks when the node is not
+    branchable.
 
-        """
+    """
     if sum(path) > max_sum or (remaining_nums_sum + sum(path)) < max_sum:
         return
     if sum(path) == max_sum:

blockchain/modular_division.py

@@ -74,13 +74,13 @@ def modular_division2(a, b, n):
 
 def extended_gcd(a, b):
     """
-    >>> extended_gcd(10, 6)
-    (2, -1, 2)
+     >>> extended_gcd(10, 6)
+     (2, -1, 2)
 
-    >>> extended_gcd(7, 5)
-    (1, -2, 3)
+     >>> extended_gcd(7, 5)
+     (1, -2, 3)
 
-   ** extended_gcd function is used when d = gcd(a,b) is required in output
+    ** extended_gcd function is used when d = gcd(a,b) is required in output
 
     """
     assert a >= 0 and b >= 0

ciphers/xor_cipher.py

@@ -21,20 +21,20 @@
 class XORCipher:
     def __init__(self, key=0):
         """
-                        simple constructor that receives a key or uses
-                        default key = 0
-                """
+        simple constructor that receives a key or uses
+        default key = 0
+        """
 
         # private field
         self.__key = key
 
     def encrypt(self, content, key):
         """
-                        input: 'content' of type string and 'key' of type int
-                        output: encrypted string 'content' as a list of chars
-                        if key not passed the method uses the key by the constructor.
-                        otherwise key = 1
-                """
+        input: 'content' of type string and 'key' of type int
+        output: encrypted string 'content' as a list of chars
+        if key not passed the method uses the key by the constructor.
+        otherwise key = 1
+        """
 
         # precondition
         assert isinstance(key, int) and isinstance(content, str)
@@ -55,11 +55,11 @@ def encrypt(self, content, key):
 
     def decrypt(self, content, key):
         """
-                        input: 'content' of type list and 'key' of type int
-                        output: decrypted string 'content' as a list of chars
-                        if key not passed the method uses the key by the constructor.
-                        otherwise key = 1
-                """
+        input: 'content' of type list and 'key' of type int
+        output: decrypted string 'content' as a list of chars
+        if key not passed the method uses the key by the constructor.
+        otherwise key = 1
+        """
 
         # precondition
         assert isinstance(key, int) and isinstance(content, list)
@@ -80,11 +80,11 @@ def decrypt(self, content, key):
 
     def encrypt_string(self, content, key=0):
         """
-                        input: 'content' of type string and 'key' of type int
-                        output: encrypted string 'content'
-                        if key not passed the method uses the key by the constructor.
-                        otherwise key = 1
-                """
+        input: 'content' of type string and 'key' of type int
+        output: encrypted string 'content'
+        if key not passed the method uses the key by the constructor.
+        otherwise key = 1
+        """
 
         # precondition
         assert isinstance(key, int) and isinstance(content, str)
@@ -105,11 +105,11 @@ def encrypt_string(self, content, key=0):
 
     def decrypt_string(self, content, key=0):
         """
-                        input: 'content' of type string and 'key' of type int
-                        output: decrypted string 'content'
-                        if key not passed the method uses the key by the constructor.
-                        otherwise key = 1
-                """
+        input: 'content' of type string and 'key' of type int
+        output: decrypted string 'content'
+        if key not passed the method uses the key by the constructor.
+        otherwise key = 1
+        """
 
         # precondition
         assert isinstance(key, int) and isinstance(content, str)
@@ -130,12 +130,12 @@ def decrypt_string(self, content, key=0):
 
     def encrypt_file(self, file, key=0):
         """
-                        input: filename (str) and a key (int)
-                        output: returns true if encrypt process was
-                        successful otherwise false
-                        if key not passed the method uses the key by the constructor.
-                        otherwise key = 1
-                """
+        input: filename (str) and a key (int)
+        output: returns true if encrypt process was
+        successful otherwise false
+        if key not passed the method uses the key by the constructor.
+        otherwise key = 1
+        """
 
         # precondition
         assert isinstance(file, str) and isinstance(key, int)
@@ -155,12 +155,12 @@ def encrypt_file(self, file, key=0):
 
     def decrypt_file(self, file, key):
         """
-                        input: filename (str) and a key (int)
-                        output: returns true if decrypt process was
-                        successful otherwise false
-                        if key not passed the method uses the key by the constructor.
-                        otherwise key = 1
-                """
+        input: filename (str) and a key (int)
+        output: returns true if decrypt process was
+        successful otherwise false
+        if key not passed the method uses the key by the constructor.
+        otherwise key = 1
+        """
 
         # precondition
         assert isinstance(file, str) and isinstance(key, int)