initial commit

.gitignore

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+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+cover/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
+# .python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# poetry
+#   Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control.
+#   This is especially recommended for binary packages to ensure reproducibility, and is more
+#   commonly ignored for libraries.
+#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
+#poetry.lock
+
+# pdm
+#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
+#pdm.lock
+#   pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it
+#   in version control.
+#   https://pdm.fming.dev/#use-with-ide
+.pdm.toml
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
+
+# PyCharm
+#  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
+#  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
+#  and can be added to the global gitignore or merged into this file.  For a more nuclear
+#  option (not recommended) you can uncomment the following to ignore the entire idea folder.
+#.idea/

algorithms/binary_search.py

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+import pytest
+
+
+def binary_search(nums: list[int], target: int):
+    low, high = 0, len(nums) - 1
+    while low <= high:
+        mid = low + (high - low) // 2
+        if nums[mid] == target:
+            return mid
+        elif nums[mid] < target:
+            low = mid + 1
+        else:
+            high = mid - 1
+    return -1
+
+
+@pytest.mark.parametrize(
+    "nums,target,expected",
+    [([*range(5)], 2, 2), ([*range(5)], 6, -1), ([*range(20, 50)], 21, 1)],
+)
+def test_binary_search(nums: list[int], target: int, expected: int):
+    assert binary_search(nums, target) == expected

leetcode/33_search_in_rotated_array.py

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+import pytest
+
+
+class Solution:
+    def search(self, nums: list[int], target: int) -> int:
+        # The first item of first ascending sequence is always bigger than the first item of the second ascending sequence.
+        low, high = 0, len(nums) - 1
+        while low <= high:
+            mid = low + (high - low) // 2
+            if nums[mid] == target:
+                return mid
+
+            # If the current item is bigger than the first item of the first ascending sequence we know that nums[low:mid] is sorted.
+            # Otherwise we know that the current mid is on the edge of the second ascending sequence.
+            if nums[mid] >= nums[low]:
+                if nums[low] <= target <= nums[mid]:
+                    high = mid - 1
+                else:
+                    low = mid + 1
+            else:
+                if nums[mid] <= target <= nums[high]:
+                    low = mid + 1
+                else:
+                    high = mid - 1
+
+        return -1
+
+
+@pytest.fixture
+def solution():
+    return Solution()
+
+
+def test_search(solution: Solution):
+    assert solution.search([4, 5, 6, 7, 0, 1, 2], 0) == 4

leetcode/34_find_first_and_last_position_of_element_in_sorted_array.py

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+import typing
+import pytest
+
+FindFn = typing.Callable[[int], bool]
+
+
+class Solution:
+    def searchRange(self, nums: list[int], target: int) -> list[int]:
+        start = self.binary_search(nums, target, lambda v: v >= target)
+        end = self.binary_search(nums, target, lambda v: v > target)
+        return [start, end]
+
+    def binary_search(self, nums: list[int], target: int, fn: FindFn) -> int:
+        res = -1
+        low, high = 0, len(nums) - 1
+        while low <= high:
+            mid = low + (high - low) // 2
+            if nums[mid] == target:
+                res = mid
+
+            if fn(nums[mid]):
+                high = mid - 1
+            else:
+                low = mid + 1
+
+        return res
+
+
+@pytest.fixture
+def solution():
+    return Solution()
+
+
+@pytest.mark.parametrize(
+    "nums, target, expected",
+    [
+        ([5, 7, 7, 8, 8, 10], 8, [3, 4]),
+        ([5, 7, 7, 8, 8, 10], 6, [-1, -1]),
+        ([], 0, [-1, -1]),
+        ([1], 1, [0, 0]),
+        ([2, 2], 2, [0, 1]),
+    ],
+)
+def test_search_range(
+    solution: Solution, nums: list[int], target: int, expected: list[int]
+):
+    assert solution.searchRange(nums, target) == expected

pytest.ini

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+[pytest]
+python_files = *.py

requirements.txt

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+pytest
+black