Open-source alternatives to 100days

This project is a comprehensive, community-maintained knowledge base and toolkit designed for competitive programming. It serves as a centralized repository for algorithmic theory, data structures, and mathematical techniques, providing a structured reference for informatics and collegiate programming competitions. The project distinguishes itself by integrating educational content with a robust suite of automation utilities. It provides a complete workflow for competitive programming, including tools for automated test case generation, solution verification, and direct interaction with onlin

This project is an algorithm template library and coding interview study guide providing reusable code patterns for common data structures and algorithms. It serves as a reference for optimized strategies and a structured learning path to build proficiency in algorithmic problem solving and competitive programming. The library focuses on standardized implementations of key algorithmic patterns, including sliding windows, backtracking, dynamic programming, and binary search. It provides specific templates for managing binary search trees, searching rotated sorted arrays, and executing divide-a

The repository provides a collection of solved algorithmic challenges and data structure implementations written in JavaScript, designed for technical interview preparation and computer science study. The content is organized as a curriculum covering standard programming problems without external dependencies. The material encompasses fundamental computer science data structures such as trees, heaps, tries, linked lists, and custom collections, alongside classical algorithms addressing arrays, strings, matrices, and graphs. Implementations also cover specialized algorithmic techniques includi

This project is a curated educational resource and solution repository for algorithmic challenges, specifically focused on LeetCode problems. It serves as a technical reference for common data structures and algorithmic patterns, providing verified code implementations across multiple programming languages alongside detailed logic and complexity analysis. The repository functions as a comprehensive study guide for competitive programming and technical interview preparation. It includes specialized learning tools such as an Anki flashcard dataset for spaced repetition and a browser extension t

This is a collection of classical algorithms and data structures implemented as a header-only C++ library. It provides a suite of tools for general algorithm implementation, including data structure management, graph theory analysis, and string processing. The library is distinguished by its specialized toolkits for cryptographic hashing and encoding, featuring implementations of MD5, SHA-1, and Base64. It also includes advanced capabilities for high-performance string processing via suffix trees and arrays, as well as computational number theory for primality testing and arbitrary-precision

This project is a data structures and algorithms library providing a collection of fifty standard code implementations for managing data and solving common computational problems. It serves as an algorithm implementation reference and study resource for educational use. The codebase covers graph theory implementations for modeling networks and performing searches, as well as string pattern matching libraries for the retrieval of character sequences. It includes a collection of hierarchical data structures, such as binary search trees and priority heaps, and provides optimized solutions for dy

This project is a comprehensive technical interview preparation resource and computer science interview guide. It serves as an educational reference for developers to study core software engineering fundamentals and common coding patterns required for employment screenings. The repository provides detailed guides and references covering data structures and algorithms, networking and security, operating systems, and web development. It specifically focuses on the implementation and complexity analysis of sorting, searching, and graph algorithms. The material encompasses a wide breadth of comp

Boost is a collection of portable, high-performance source libraries that extend the C++ standard library. It provides a wide range of reusable components, data structures, and algorithms designed to add capabilities to the base language across different platforms. The project is distinguished by its extensive focus on compile-time template metaprogramming and generic programming. It implements advanced architectural patterns such as policy-based design, concept-based type validation, and the use of SFINAE for conditional template resolution to minimize runtime overhead. The library covers a

This project is a collection of optimized computational routines and standardized implementations of fundamental computer science algorithms. It serves as an educational library for studying and applying core algorithmic patterns, including dynamic programming, greedy strategies, and recursive decomposition, within a TypeScript environment. The library distinguishes itself by providing generalized solvers for complex optimization and analysis tasks. It includes specific implementations for resource allocation, such as rod cutting, interval scheduling, and change-making problems, alongside seq

This project is a collection of foundational machine learning algorithms and tools implemented from scratch in Python. It serves as a library of core implementations for regression, classification, and clustering models, designed to demonstrate the underlying mathematical structures of these algorithms without relying on high-level machine learning frameworks. The project focuses on the manual implementation of algorithmic logic, including neural networks with forward propagation and weight updates, as well as various supervised and unsupervised learning models. It utilizes NumPy for vectoriz

DataFrame is a C++ tabular data library and manipulation engine designed for managing heterogeneous data in contiguous memory. It functions as a statistical analysis framework and time series analysis toolkit, providing the means to store, index, and transform multidimensional datasets. The project distinguishes itself through a high-performance execution model that utilizes column-major storage, SIMD-aligned memory allocation, and a thread-pool for parallel computations. It employs a visitor-based algorithm dispatch system and policy-driven transformations to decouple data processing logic f

This project is a curated reference library of algorithmic patterns, data structure implementations, and system design notes. It serves as a Java algorithmic problem set and a competitive programming guide, providing a collection of solutions for coding challenges from platforms like LeetCode and LintCode. The library is distinguished by its comprehensive set of Java implementations for advanced data structures and algorithmic strategies. It includes detailed references for solving complex problems with accompanying time and space complexity analysis. The project covers a broad surface of co

This project is a pedagogical implementation of a hash table in C, built from scratch using open addressing and linear probing for collision resolution. It serves as a computer science algorithm demo, demonstrating how to construct a fundamental key-value store at a low level. The implementation covers the core operations of an associative array: inserting a key-value pair, looking up a value by its key, and deleting a pair. It uses a hash function to compute storage locations, maps hash values to array indices with the modulo operator, and resolves collisions by scanning sequentially through

This project is an educational repository and collection of algorithms implemented in C++. It provides a structured set of code examples covering mathematics, computer science, and physics for reference and learning. The collection includes implementations of data structures for managing hierarchical and linear data, such as binary search trees and AVL trees. It also features simulations of computer science concepts, including CPU scheduling and the resolution of combinatorial puzzles. The repository further covers cryptographic examples through the implementation of classic encryption and e

This project serves as a centralized knowledge base and study guide for mastering computer science fundamentals and technical interview preparation. It provides a structured collection of algorithmic implementations, data structure guides, and theoretical references designed to support professional development and problem-solving skills. The repository distinguishes itself through a taxonomy-based organization that maps complex concepts into a hierarchical structure. It standardizes the expression of abstract data structures and algorithms using a consistent programming language, with impleme

Dragonfly is a high-performance, multi-model in-memory data store designed to serve as a drop-in replacement for existing database infrastructures. By utilizing a multi-threaded, shared-nothing architecture and a fiber-based concurrency model, it maximizes CPU utilization and minimizes latency for read and write operations. The system supports a wide range of data structures, including strings, hashes, lists, sets, sorted sets, and JSON documents, while maintaining full compatibility with standard industry wire protocols and client libraries. What distinguishes Dragonfly is its focus on effic

This repository provides a collection of fundamental computer science algorithms and data structures implemented in Go. It serves as a technical reference and educational resource, offering reusable modules for common computational tasks including data organization, graph analysis, and numerical operations. The library distinguishes itself through the application of idiomatic Go patterns, utilizing generics for type abstraction and interface-driven polymorphism to ensure compile-time type safety. It emphasizes algorithmic efficiency by employing in-place memory mutation to reduce allocations

This is a collection of standard data structures and algorithmic implementations written in Rust. It provides a suite of specialized libraries designed for competitive programming and systems engineering. The project is organized into distinct toolkits for graph theory, number theory, range queries, and string processing. It includes implementations for computing shortest paths and network flows, performing primality tests and modular arithmetic, and managing associative range queries. The library covers broad computational areas including signal processing via fast Fourier transforms, text

This project is a comprehensive reference for algorithms and data structures used to solve complex computational problems in competitive programming. It serves as a technical resource for implementing advanced mathematical programming, computational geometry, and graph theory. The repository provides detailed implementation guides for diversifying algorithmic techniques, including top-down and bottom-up dynamic programming optimization, number theory, and linear algebra. It features specific guides for complex tasks such as constructing planar graphs, solving linear Diophantine equations, and

This is a Python machine learning library featuring a collection of core algorithms implemented from scratch to demonstrate foundational AI concepts. It provides a comprehensive toolkit for supervised learning, unsupervised learning, and neural network development. The project is distinguished by its custom implementation of a neural network framework, which includes multi-layer perceptrons with backpropagation, gradient descent, and weight regularization. It also includes a specialized anomaly detection toolkit that identifies outliers and rare events using Gaussian probability distributions

This project is a JavaScript sorting algorithm library and educational programming resource. It provides a collection of classic sorting implementations designed to teach the logic behind common data ordering techniques. The project serves as a technical reference guide, offering implementations of various sorting methods alongside explanations of their time and space complexity. It focuses on the application of fundamental computer science patterns within a JavaScript environment. The library covers a wide range of sorting algorithms, including comparison-based methods like quicksort, merge

This project is a comprehensive repository of fundamental computer science algorithms and data structures designed as a reference for academic study, technical interview preparation, and competitive programming. It provides standardized implementations of core computational strategies, serving as an educational resource for developers to master software engineering fundamentals and algorithmic problem-solving. The collection distinguishes itself through a multi-language approach, offering cross-language solutions for complex tasks ranging from graph traversal and dynamic programming to bitwis

This repository is a structured educational archive of classic computer science algorithms and data structures implemented in Python. It serves as a reference library designed for study and technical skill development, providing clean, readable examples of fundamental computational techniques rather than production-ready software components. The project distinguishes itself through its idiomatic approach, utilizing native language features and standard library conventions to demonstrate algorithmic logic clearly. Each implementation is organized into a hierarchical directory structure that mi

This repository is a comprehensive collection of fully worked solutions to exercises and problems from the standard algorithms textbook by Cormen, Leiserson, Rivest, and Stein (CLRS). It serves as an educational reference for algorithm design and analysis, providing step-by-step reasoning, pseudocode, and mathematical proofs for a wide range of topics. The content spans core computer science areas: algorithm analysis with asymptotic notation, recurrence solving, and amortized cost analysis; data structure implementation and operations for binary search trees, red-black trees, B-trees, Fibonac

algorithm-base is an educational library and study guide designed for simulating algorithms and studying data structures. It functions as an execution visualizer that renders step-by-step state changes and pointer updates through animated simulations to illustrate how data movement works. The project distinguishes itself by mapping conceptual logic directly to multi-language source code implementations. It utilizes a comparative analysis framework to evaluate different algorithmic strategies based on stability, time complexity, and space complexity, while organizing problems by underlying mec

pysheeet is a technical reference library providing a curated collection of code snippets and implementation patterns for advanced Python development, system integration, and high-performance computing. It serves as a comprehensive guide for implementing low-level network programming, native C extensions, and asynchronous and concurrent programming. The project provides specialized frameworks for the development and deployment of large language models, including tools for distributed GPU inference and high-performance serving. It also includes detailed patterns for high-performance computing

This repository serves as a comprehensive library for algorithmic problem solving, providing reference implementations for fundamental computer science challenges. It is designed as a resource for technical interview preparation and competitive programming training, focusing on the mastery of common patterns and data structures required for coding assessments. The project distinguishes itself by offering solutions that emphasize idiomatic Python usage and performance optimization. It covers a wide range of algorithmic techniques, including greedy selection, dynamic programming, graph theory,