How to Design a Heap (Priority Queue) from Scratch in Java

·2 views

A technical guide published on DEV Community walks software engineers and Java developers through the low-level design of a Heap data structure, targeting those preparing for system design or SDE interviews. The article covers core heap concepts including Min Heap and Max Heap properties, array-based internal representation, and parent-child index formulas. It details the implementation of key operations such as insert with heapify-up, remove with heapify-down, peek, and buildHeap, along with their time complexities. A complete Java MinHeap class is provided, demonstrating dynamic resizing, edge-case handling, and O(n) heap construction. The guide also touches on Java's built-in PriorityQueue internals and suggests design improvements like custom Comparator support and decreaseKey operations.

Read the full story at DEV Community

This is an AI-generated summary. ShortSingh links to the original source for the complete article.

Discussion (0)

Solo Developers Turn to Micro-SaaS Utility Tools for Passive Income in 2026

Advances in AI coding assistants and accessible cloud infrastructure have made it possible for a single developer to build and launch a software product within weeks, without venture capital or a large team. Developers are increasingly focusing on micro-SaaS utility platforms — simple, single-purpose tools such as image compressors or JSON formatters — that attract high search-engine traffic rather than requiring upfront payment from users. These platforms are typically monetized through display advertising, affiliate links, or freemium tiers for heavy usage. A recommended 2026 tech stack includes Next.js with Tailwind CSS for the frontend, local AI models like Llama 3 for rapid code generation, and automation tools such as n8n for workflow management. Structuring a platform around multiple standalone micro-tools allows each utility to target specific search keywords independently, improving organic visibility and making it easier to add new tools over time.

0 comments Read more at DEV Community

ProgrammingDEV Community ·

How to Manage TLS Certificates for Internal Services in a DevOps Environment

Many organizations secure only public-facing endpoints, leaving internal service-to-service traffic vulnerable to eavesdropping and tampering. TLS certificates address this by providing confidentiality, data integrity, and mutual authentication between internal services. Managing TLS at scale internally is challenging due to the volume of services, automation needs, and the impracticality of using costly public Certificate Authorities. The recommended solution is to build an internal Public Key Infrastructure (PKI) with a private Root CA and intermediate CAs for different environments or purposes. Tools such as HashiCorp Vault and open-source options like Smallstep step-ca can automate certificate issuance, renewal, and revocation within a zero-trust security framework.

0 comments Read more at DEV Community

ProgrammingDEV Community ·

Hyper: Open-Source Distributed Firecracker MicroVM Orchestrator Built in Elixir

A developer has released Hyper, a free and open-source distributed microVM orchestrator built on Elixir and the BEAM runtime, addressing the lack of open alternatives in a market dominated by paid, closed-source SaaS products. Hyper is designed to run across clusters of bare-metal machines and supports gRPC for non-BEAM clients, making it broadly accessible. The project offers fast cold boots under one second, copy-on-write filesystem forking in roughly 50 milliseconds, and live VM management via an interactive Elixir REPL. Licensed under MIT, Hyper requires only a sidecar Postgres instance and keeps its privileged attack surface minimal through a single setuid Rust helper. The software is still in active testing, with planned additions including automatic cloud provisioning, expanded test coverage, and improved documentation.

0 comments Read more at DEV Community

ProgrammingDEV Community ·

How to Use Cursor AI as an Architectural Tool, Not Just a Code Generator

A developer guide published on DEV Community argues that users of Cursor AI should shift their mindset from writing code to supervising architecture, treating the tool like a junior developer that needs structural direction. The article recommends configuring MCP plugins, particularly a server called 'superpowers', to enforce structured planning and test-driven development before any code is generated. A practical setup involves adding the plugin via a .cursor/mcp.json file, which prompts users to define behaviors, edge cases, and module boundaries upfront. The guide also introduces a 'caveman mode' rule added to the .cursorrules file, which strips AI responses of unnecessary filler text to preserve context window space during fast coding sessions. The core argument is that skipping the planning phase and prompting at the implementation level leads to inconsistent, hard-to-maintain codebases.

0 comments Read more at DEV Community