Merge branch 'TheAlgorithms:master' into binary_operations

Author: sudiptiwari

.pre-commit-config.yaml

@@ -51,7 +51,7 @@ repos:
       - id: validate-pyproject
 
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.5.1
+    rev: v1.6.0
     hooks:
       - id: mypy
         args:

DIRECTORY.md

@@ -532,6 +532,7 @@
   * [Logistic Regression](machine_learning/logistic_regression.py)
   * Loss Functions
     * [Binary Cross Entropy](machine_learning/loss_functions/binary_cross_entropy.py)
+    * [Categorical Cross Entropy](machine_learning/loss_functions/categorical_cross_entropy.py)
     * [Huber Loss](machine_learning/loss_functions/huber_loss.py)
     * [Mean Squared Error](machine_learning/loss_functions/mean_squared_error.py)
   * [Mfcc](machine_learning/mfcc.py)

blockchain/diophantine_equation.py

@@ -83,7 +83,8 @@ def extended_gcd(a: int, b: int) -> tuple[int, int, int]:
     (1, -2, 3)
 
     """
-    assert a >= 0 and b >= 0
+    assert a >= 0
+    assert b >= 0
 
     if b == 0:
         d, x, y = a, 1, 0
@@ -92,7 +93,8 @@ def extended_gcd(a: int, b: int) -> tuple[int, int, int]:
         x = q
         y = p - q * (a // b)
 
-    assert a % d == 0 and b % d == 0
+    assert a % d == 0
+    assert b % d == 0
     assert d == a * x + b * y
 
     return (d, x, y)

boolean_algebra/imply_gate.py

@@ -0,0 +1,40 @@
+"""
+An IMPLY Gate is a logic gate in boolean algebra which results to 1 if
+either input 1 is 0, or if input 1 is 1, then the output is 1 only if input 2 is 1.
+It is true if input 1 implies input 2.
+
+Following is the truth table of an IMPLY Gate:
+    ------------------------------
+    | Input 1 | Input 2 | Output |
+    ------------------------------
+    |    0    |    0    |    1   |
+    |    0    |    1    |    1   |
+    |    1    |    0    |    0   |
+    |    1    |    1    |    1   |
+    ------------------------------
+
+Refer - https://en.wikipedia.org/wiki/IMPLY_gate
+"""
+
+
+def imply_gate(input_1: int, input_2: int) -> int:
+    """
+    Calculate IMPLY of the input values
+
+    >>> imply_gate(0, 0)
+    1
+    >>> imply_gate(0, 1)
+    1
+    >>> imply_gate(1, 0)
+    0
+    >>> imply_gate(1, 1)
+    1
+    """
+    return int(input_1 == 0 or input_2 == 1)
+
+
+if __name__ == "__main__":
+    print(imply_gate(0, 0))
+    print(imply_gate(0, 1))
+    print(imply_gate(1, 0))
+    print(imply_gate(1, 1))

boolean_algebra/nimply_gate.py

@@ -0,0 +1,40 @@
+"""
+An NIMPLY Gate is a logic gate in boolean algebra which results to 0 if
+either input 1 is 0, or if input 1 is 1, then it is 0 only if input 2 is 1.
+It is false if input 1 implies input 2. It is the negated form of imply
+
+Following is the truth table of an NIMPLY Gate:
+    ------------------------------
+    | Input 1 | Input 2 | Output |
+    ------------------------------
+    |    0    |    0    |    0   |
+    |    0    |    1    |    0   |
+    |    1    |    0    |    1   |
+    |    1    |    1    |    0   |
+    ------------------------------
+
+Refer - https://en.wikipedia.org/wiki/NIMPLY_gate
+"""
+
+
+def nimply_gate(input_1: int, input_2: int) -> int:
+    """
+    Calculate NIMPLY of the input values
+
+    >>> nimply_gate(0, 0)
+    0
+    >>> nimply_gate(0, 1)
+    0
+    >>> nimply_gate(1, 0)
+    1
+    >>> nimply_gate(1, 1)
+    0
+    """
+    return int(input_1 == 1 and input_2 == 0)
+
+
+if __name__ == "__main__":
+    print(nimply_gate(0, 0))
+    print(nimply_gate(0, 1))
+    print(nimply_gate(1, 0))
+    print(nimply_gate(1, 1))

ciphers/xor_cipher.py

@@ -38,7 +38,8 @@ def encrypt(self, content: str, key: int) -> list[str]:
         """
 
         # precondition
-        assert isinstance(key, int) and isinstance(content, str)
+        assert isinstance(key, int)
+        assert isinstance(content, str)
 
         key = key or self.__key or 1
 
@@ -56,7 +57,8 @@ def decrypt(self, content: str, key: int) -> list[str]:
         """
 
         # precondition
-        assert isinstance(key, int) and isinstance(content, list)
+        assert isinstance(key, int)
+        assert isinstance(content, list)
 
         key = key or self.__key or 1
 
@@ -74,7 +76,8 @@ def encrypt_string(self, content: str, key: int = 0) -> str:
         """
 
         # precondition
-        assert isinstance(key, int) and isinstance(content, str)
+        assert isinstance(key, int)
+        assert isinstance(content, str)
 
         key = key or self.__key or 1
 
@@ -99,7 +102,8 @@ def decrypt_string(self, content: str, key: int = 0) -> str:
         """
 
         # precondition
-        assert isinstance(key, int) and isinstance(content, str)
+        assert isinstance(key, int)
+        assert isinstance(content, str)
 
         key = key or self.__key or 1
 
@@ -125,7 +129,8 @@ def encrypt_file(self, file: str, key: int = 0) -> bool:
         """
 
         # precondition
-        assert isinstance(file, str) and isinstance(key, int)
+        assert isinstance(file, str)
+        assert isinstance(key, int)
 
         try:
             with open(file) as fin, open("encrypt.out", "w+") as fout:
@@ -148,7 +153,8 @@ def decrypt_file(self, file: str, key: int) -> bool:
         """
 
         # precondition
-        assert isinstance(file, str) and isinstance(key, int)
+        assert isinstance(file, str)
+        assert isinstance(key, int)
 
         try:
             with open(file) as fin, open("decrypt.out", "w+") as fout:

conversions/decimal_to_hexadecimal.py

@@ -57,7 +57,8 @@ def decimal_to_hexadecimal(decimal: float) -> str:
     >>> decimal_to_hexadecimal(-256) == hex(-256)
     True
     """
-    assert type(decimal) in (int, float) and decimal == int(decimal)
+    assert isinstance(decimal, (int, float))
+    assert decimal == int(decimal)
     decimal = int(decimal)
     hexadecimal = ""
     negative = False

data_structures/arrays/find_triplets_with_0_sum.py

@@ -0,0 +1,24 @@
+from itertools import combinations
+
+
+def find_triplets_with_0_sum(nums: list[int]) -> list[list[int]]:
+    """
+    Given a list of integers, return elements a, b, c such that a + b + c = 0.
+    Args:
+        nums: list of integers
+    Returns:
+        list of lists of integers where sum(each_list) == 0
+    Examples:
+        >>> find_triplets_with_0_sum([-1, 0, 1, 2, -1, -4])
+        [[-1, -1, 2], [-1, 0, 1]]
+        >>> find_triplets_with_0_sum([])
+        []
+        >>> find_triplets_with_0_sum([0, 0, 0])
+        [[0, 0, 0]]
+        >>> find_triplets_with_0_sum([1, 2, 3, 0, -1, -2, -3])
+        [[-3, 0, 3], [-3, 1, 2], [-2, -1, 3], [-2, 0, 2], [-1, 0, 1]]
+    """
+    return [
+        list(x)
+        for x in sorted({abc for abc in combinations(sorted(nums), 3) if not sum(abc)})
+    ]

data_structures/arrays/pairs_with_given_sum.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+
+"""
+Given an array of integers and an integer req_sum, find the number of pairs of array
+elements whose sum is equal to req_sum.
+
+https://practice.geeksforgeeks.org/problems/count-pairs-with-given-sum5022/0
+"""
+from itertools import combinations
+
+
+def pairs_with_sum(arr: list, req_sum: int) -> int:
+    """
+    Return the no. of pairs with sum "sum"
+    >>> pairs_with_sum([1, 5, 7, 1], 6)
+    2
+    >>> pairs_with_sum([1, 1, 1, 1, 1, 1, 1, 1], 2)
+    28
+    >>> pairs_with_sum([1, 7, 6, 2, 5, 4, 3, 1, 9, 8], 7)
+    4
+    """
+    return len([1 for a, b in combinations(arr, 2) if a + b == req_sum])
+
+
+if __name__ == "__main__":
+    from doctest import testmod
+
+    testmod()

data_structures/binary_tree/binary_search_tree_recursive.py

@@ -12,6 +12,8 @@
 import unittest
 from collections.abc import Iterator
 
+import pytest
+
 
 class Node:
     def __init__(self, label: int, parent: Node | None) -> None:
@@ -78,7 +80,7 @@ def _put(self, node: Node | None, label: int, parent: Node | None = None) -> Nod
                 node.right = self._put(node.right, label, node)
             else:
                 msg = f"Node with label {label} already exists"
-                raise Exception(msg)
+                raise ValueError(msg)
 
         return node
 
@@ -95,14 +97,14 @@ def search(self, label: int) -> Node:
         >>> node = t.search(3)
         Traceback (most recent call last):
             ...
-        Exception: Node with label 3 does not exist
+        ValueError: Node with label 3 does not exist
         """
         return self._search(self.root, label)
 
     def _search(self, node: Node | None, label: int) -> Node:
         if node is None:
             msg = f"Node with label {label} does not exist"
-            raise Exception(msg)
+            raise ValueError(msg)
         else:
             if label < node.label:
                 node = self._search(node.left, label)
@@ -124,7 +126,7 @@ def remove(self, label: int) -> None:
         >>> t.remove(3)
         Traceback (most recent call last):
             ...
-        Exception: Node with label 3 does not exist
+        ValueError: Node with label 3 does not exist
         """
         node = self.search(label)
         if node.right and node.left:
@@ -179,7 +181,7 @@ def exists(self, label: int) -> bool:
         try:
             self.search(label)
             return True
-        except Exception:
+        except ValueError:
             return False
 
     def get_max_label(self) -> int:
@@ -190,15 +192,15 @@ def get_max_label(self) -> int:
         >>> t.get_max_label()
         Traceback (most recent call last):
             ...
-        Exception: Binary search tree is empty
+        ValueError: Binary search tree is empty
 
         >>> t.put(8)
         >>> t.put(10)
         >>> t.get_max_label()
         10
         """
         if self.root is None:
-            raise Exception("Binary search tree is empty")
+            raise ValueError("Binary search tree is empty")
 
         node = self.root
         while node.right is not None:
@@ -214,15 +216,15 @@ def get_min_label(self) -> int:
         >>> t.get_min_label()
         Traceback (most recent call last):
             ...
-        Exception: Binary search tree is empty
+        ValueError: Binary search tree is empty
 
         >>> t.put(8)
         >>> t.put(10)
         >>> t.get_min_label()
         8
         """
         if self.root is None:
-            raise Exception("Binary search tree is empty")
+            raise ValueError("Binary search tree is empty")
 
         node = self.root
         while node.left is not None:
@@ -359,7 +361,7 @@ def test_put(self) -> None:
         assert t.root.left.left.parent == t.root.left
         assert t.root.left.left.label == 1
 
-        with self.assertRaises(Exception):  # noqa: B017
+        with pytest.raises(ValueError):
             t.put(1)
 
     def test_search(self) -> None:
@@ -371,7 +373,7 @@ def test_search(self) -> None:
         node = t.search(13)
         assert node.label == 13
 
-        with self.assertRaises(Exception):  # noqa: B017
+        with pytest.raises(ValueError):
             t.search(2)
 
     def test_remove(self) -> None:
@@ -517,7 +519,7 @@ def test_get_max_label(self) -> None:
         assert t.get_max_label() == 14
 
         t.empty()
-        with self.assertRaises(Exception):  # noqa: B017
+        with pytest.raises(ValueError):
             t.get_max_label()
 
     def test_get_min_label(self) -> None:
@@ -526,7 +528,7 @@ def test_get_min_label(self) -> None:
         assert t.get_min_label() == 1
 
         t.empty()
-        with self.assertRaises(Exception):  # noqa: B017
+        with pytest.raises(ValueError):
             t.get_min_label()
 
     def test_inorder_traversal(self) -> None: