"Simplicity is the soul of efficiency."

I am a software engineer with a deep fascination for solving complex algorithmic problems and securing modern digital ecosystems. My journey spans backend architecture, full-stack web platforms, DSA roadmaps, and ethical hacking.

• 🎯 Current Focus: Architecting high-performance backend systems with Java & Spring Boot while exploring offensive security and penetration testing.
• 🧠 Data Structures & Algorithms: Active solver and curator of algorithmic patterns in DSA — compiling real-world company-wise question sheets.
• 🔐 Ethical Hacking: Hands-on with Linux systems, network security scanning, automation scripting in Bash/Python, and active CTFs on TryHackMe.
• 🚀 Flagship Projects: Creator of DSA Doctor (company-wise question banks) and author of the DSA Logic Building Playbook (step-by-step thinking framework).

DSA Doctor (live at dsadoctor.com) is a comprehensive coding interview preparation platform engineered to help software developers, engineering students, and tech aspirants conquer Data Structures & Algorithms (DSA) through curated, company-wise interview questions.

Whether you search for DSA Doctor, dsa doctor, or dsadoctor, this platform serves as an all-in-one diagnostic and practice guide to ace technical interviews, coding assessments, and software engineering placements at top tech companies.

• 🏢 Company-Wise Question Banks: Practice real-world coding problems asked by top-tier tech companies including Google, Microsoft, Amazon, Meta, Apple, Netflix, Uber, Atlassian, Adobe, and many more.
• 🎯 Pattern-Based DSA Roadmaps: Structured learning tracks covering core algorithmic patterns — Arrays, Two Pointers, Sliding Window, Dynamic Programming, Graphs, Trees, and Recursion.
• ⚡ Interactive Real-Time Filters: Effortlessly filter questions by company, difficulty level (Easy, Medium, Hard), core data structure topics, and appearance frequency.
• 🔗 Direct LeetCode Integration: Immediate access to verified LeetCode problem links with optimal time and space complexity guidelines.
• 🌙 Modern Glassmorphic Dark UI: High-performance, distraction-free interface with instant search and dark/light mode for daily coding sessions.

🌐 Live Website: https://dsadoctor.com
📂 GitHub Repository: Kali-Prem/leetcode-company-wise-interview-questions
🏷️ Search Tags: DSA Doctor • dsa doctor • dsadoctor.com • dsadoctor • company-wise DSA interview questions • LeetCode company-wise problems • coding interview preparation • DSA roadmap • Prem Kumar DSA Doctor

"Zyada log DSA me code nahi, logic me atakte hain." — A battle-tested mental framework to develop problem-solving intuition without memorizing solutions.

The DSA Logic Building Playbook is a complete masterclass engineered to take you from reading an unseen problem statement to writing clean, optimal Java code:

• 🪜 The 7-Step Blueprint: A universal step-by-step thinking framework for dissecting any coding problem from comprehension to code.
• 🧪 Deriving Patterns from Test Cases: How to dry-run manual test cases on paper to identify underlying algorithmic rules and mathematical invariants.
• ⚡ From Brute Force to Optimal: Systematic waste identification — converting naive $O(N^2)$ checks into optimal data structures.
• ⏱️ Constraint Decoding: Predicting the target time complexity directly from input size N before writing code.
• 🔑 Keyword-to-Pattern Cheat Sheet: 18 direct problem keywords mapped instantly to core algorithmic paradigms.
• 💻 8 Step-by-Step Worked Examples: Complete walkthroughs in Java from manual trace to production code.

📂 Repository: Kali-Prem/dsa-logic-building-playbook
🎬 Video Walkthrough: Watch Full Video on YouTube
🏷️ Topics: DSA Logic Building • Interview Preparation • Java DSA • Pattern Solving • Mental Models

• 🌟 dsa-logic-building-playbook (⭐ Master Playbook): The definitive mental framework teaching how to build logic in DSA problems. Learn how to derive patterns directly from test cases, eliminate brute force bottlenecks, decode constraints, and implement optimal solutions in clean Java. Includes 8 worked examples and video walkthrough!
• 500-DSA-Pattern-Problems: A curated and highly organized compilation of 500+ DSA pattern problems, designed to master problem-solving paradigms for top-tier coding interviews.
• Java-DSA-Learning: Core Java implementations of fundamental data structures, custom algorithm optimizations, and step-by-step guides.
• leetcode-company-wise-interview-questions (Official Repository for DSA Doctor): Targeted study lists and company-wise curated question sheets powering the live platform at dsadoctor.com.

• Hacking-Learning: Comprehensive reference sheets, ethical hacking labs, vulnerability assessment guides, and custom network security scripts.

• TeamUp-Ai: An intelligent, AI-powered project matching and team-building platform designed for developers and hackathons.
• FSWD-Learning: Hands-on learning paths covering responsive frontend design systems and robust RESTful microservice architectures.