Python算法大全，用 Python 实现的所有算法

# Project Euler Problems are taken from https://projecteuler.net/, the Project Euler. [Problems are licensed under CC BY-NC-SA 4.0](https://projecteuler.net/copyright). Project Euler is a series of challenging mathematical/computer programming problems that require more than just mathematical insights to solve. Project Euler is ideal for mathematicians who are learning to code. The solutions will be checked by our [automated testing on GitHub Actions](https://github.com/TheAlgorithms/Python/actions) with the help of [this script](https://github.com/TheAlgorithms/Python/blob/master/scripts/validate_solutions.py). The efficiency of your code is also checked. You can view the top 10 slowest solutions on GitHub Actions logs (under `slowest 10 durations`) and open a pull request to improve those solutions. ## Solution Guidelines Welcome to [TheAlgorithms/Python](https://github.com/TheAlgorithms/Python)! Before reading the solution guidelines, make sure you read the whole [Contributing Guidelines](https://github.com/TheAlgorithms/Python/blob/master/CONTRIBUTING.md) as it won't be repeated in here. If you have any doubt on the guidelines, please feel free to [state it clearly in an issue](https://github.com/TheAlgorithms/Python/issues/new) or ask the community in [Gitter](https://gitter.im/TheAlgorithms). You can use the [template](https://github.com/TheAlgorithms/Python/blob/master/project_euler/README.md#solution-template) we have provided below as your starting point but be sure to read the [Coding Style](https://github.com/TheAlgorithms/Python/blob/master/project_euler/README.md#coding-style) part first. ### Coding Style * Please maintain consistency in project directory and solution file names. Keep the following points in mind: * Create a new directory only for the problems which do not exist yet. * If you create a new directory, please create an empty `__init__.py` file inside it as well. * Please name the project **directory** as `problem_<problem_number>` where `problem_number` should be filled with 0s so as to occupy 3 digits. Example: `problem_001`, `problem_002`, `problem_067`, `problem_145`, and so on. * Please provide a link to the problem and other references, if used, in the **module-level docstring**. * All imports should come ***after*** the module-level docstring. * You can have as many helper functions as you want but there should be one main function called `solution` which should satisfy the conditions as stated below: * It should contain positional argument(s) whose default value is the question input. Example: Please take a look at [Problem 1](https://projecteuler.net/problem=1) where the question is to *Find the sum of all the multiples of 3 or 5 below 1000.* In this case the main solution function will be `solution(limit: int = 1000)`. * When the `solution` function is called without any arguments like so: `solution()`, it should return the answer to the problem. * Every function, which includes all the helper functions, if any, and the main solution function, should have `doctest` in the function docstring along with a brief statement mentioning what the function is about. * There should not be a `doctest` for testing the answer as that is done by our GitHub Actions build using this [script](https://github.com/TheAlgorithms/Python/blob/master/scripts/validate_solutions.py). Keeping in mind the above example of [Problem 1](https://projecteuler.net/problem=1): ```python def solution(limit: int = 1000): """ A brief statement mentioning what the function is about. You can have a detailed explanation about the solution method in the module-level docstring. >>> solution(1) ... >>> solution(16) ... >>> solution(100) ... """ ``` ### Solution Template You can use the below template as your starting point but please read the [Coding Style](https://github.com/TheAlgorithms/Python/blob/master/project_euler/README.md#coding-style) first to understand how the template works. Please change the name of the helper functions accordingly, change the parameter names with a descriptive one, replace the content within `[square brackets]` (including the brackets) with the appropriate content. ```python """ Project Euler Problem [problem number]: [link to the original problem] ... [Entire problem statement] ... ... [Solution explanation - Optional] ... References [Optional]: - [Wikipedia link to the topic] - [Stackoverflow link] ... """ import module1 import module2 ... def helper1(arg1: [type hint], arg2: [type hint], ...) -> [Return type hint]: """ A brief statement explaining what the function is about. ... A more elaborate description ... [Optional] ... [Doctest] ... """ ... # calculations ... return # You can have multiple helper functions but the solution function should be # after all the helper functions ... def solution(arg1: [type hint], arg2: [type hint], ...) -> [Return type hint]: """ A brief statement mentioning what the function is about. You can have a detailed explanation about the solution in the module-level docstring. ... [Doctest as mentioned above] ... """ ... # calculations ... return answer if __name__ == "__main__": print(f"{solution() = }") ```