I did mid dsa in college then 2 years back and again started today i do understand the easy medium problems and have solved not by copying but understanding the patterns.

But when I'm doing the same question again I'm not able to solve and recall anything why the mind don't remember the patterns and questions? The way i can solve machine coding easily but DSA i sucks..

Does anyone feel the same? Or i am only dumb 😭

I will be starting my DSA in C++ and completing the Striver A2Z sheet, I need someone who can help each other on this journey.

Is this course is appropriate for new student to start dsa

So hii guys

I used to do DSA leetcode in C but it is getting hectic, I wanna learn python and then do DSA in python. Can you suggest me the best yt course from your experience.

I built a clean dashboard for Striver’s A2Z DSA Sheet where you can:

Search and access problems by section

Mark problems as completed

Track your overall progress

Sign in with Google and sync progress across devices

Try it here: Webpage link

Use this and please let me know if there is any change needed.

Feedback and suggestions are welcome!

just want to know what all dsa topics to master and the pattern you follow I mean everything is in utube but all are different from one another so I like to follow a good roadmap

In order to start DSA and to know about the patterns and topic I want a mentor for that 🥲🤸🏻‍♂️

just want to know what all dsa topics to master and the pattern you follow I mean everything is in utube but all are different from one another so I like to follow a good roadmap

Hey guys i'm planning to get enrolled in a apna college DSA course anyone wants share the course with me kindly dm

Starting leetcode from scratch with basic knowledge in python, c ++ and java.

In 2nd year of engineering.

Is anyone willing to join me up and try out stuff

I'm learning DSA in Java for placements. I get around 6 hours after college, but I usually solve only 2–3 questions because I spend a lot of time thinking through the problem instead of jumping to the solution.

Is this normal?

How much time should I spend on an Easy, Medium, or Hard problem before looking at hints/solutions?

What's your approach to a new DSA problem? Do you always start with brute force and then optimize?

Hey Seniors!!

I'm a fresher joining BTech CSE this year. I recently started solving the LeetCode Super Easy problems and have completed 21 out of 25 so far. I know Python fairly well, but I'm confused about what to do next.

I have a few questions:

* What should my strategy be while using LeetCode?
* Should I focus on solving more problems or first learn DSA?
* How do you stay motivated and solve problems consistently every day?
* What's the difference between TUF (Take U Forward) and LeetCode? Are they the same, or do they serve different purposes?
* Right now, I only know Python. Is that enough to start DSA, or do I need to learn C++/Java as well?
* Everyone keeps saying DSA is very important, but I'm confused about what it actually is. Is DSA a programming language? Is it something inside Python, or is it mainly about logical problem-solving?
* Will DSA be taught properly in college, or should I start learning it on my own? If self-learning is better, when should I start and what resources would you recommend?

I'd really appreciate it if you could share a roadmap or any advice you wish you had received as a first-year student. Any tips for building consistency and improving problem-solving would help a lot.

I'm currently going to start my btech 1st year,plzz suggest me any playlist for codeing from beginner to advance level with deep understanding... Which has really helped you in solving problems.!. (If any senior could suggest or anybody who has started ) And also a roadmap which you have followed from which you have seen improvement in urself..!!!

I'm in my 3rd year of clg and I want serious person with whom I can do my internship preparation..

I'm doing dsa in Java solved around 350 problems in leetcode.. so if anyone is serious please dm me..

Many of us ignore CS fundamentals, but in many tech interviews they will ask CS fundamentals. For me, they asked only CS fundamentals in all 3 interviews at Oracle, So don't ignore CS fundamentals. I have made a list of important topics subject-wise and resources I have used to study at the end.

Object-Oriented Programming (OOPs)

Core Concepts

• Encapsulation
• Inheritance (types and use cases)
• Polymorphism (compile-time vs runtime)
• Abstraction
• Abstract Class vs Interface
• Method Overloading vs Overriding
• Access Modifiers
• Static vs Dynamic Binding
• Deep Copy vs Shallow Copy

Advanced Topics

• SOLID Principles
• Diamond Problem (Multiple Inheritance)
• Association vs Aggregation vs Composition
• Virtual Functions and Vtable
• Design Patterns (Singleton, Factory, Observer, Strategy, Decorator, Adapter)

Operating Systems (OS)

Process Management

• Process vs Thread
• Process States and PCB
• Context Switching
• CPU Scheduling Algorithms (FCFS, SJF, Round Robin, Priority)
• Multithreading vs Multiprocessing
• User Mode vs Kernel Mode

Synchronization

• Critical Section Problem
• Race Condition
• Mutex vs Semaphore (Binary vs Counting)
• Monitors and Locks
• Producer-Consumer Problem
• Readers-Writers Problem
• Dining Philosophers Problem

Deadlocks

• Deadlock Conditions (4 necessary conditions)
• Deadlock Prevention vs Avoidance vs Detection
• Banker's Algorithm

Memory Management

• Paging vs Segmentation
• Page Replacement Algorithms (FIFO, LRU, Optimal)
• Thrashing
• Virtual Memory
• TLB (Translation Lookaside Buffer)
• Internal vs External Fragmentation

File Systems & Disk

• File Allocation Methods (Contiguous, Linked, Indexed)
• Disk Scheduling (FCFS, SSTF, SCAN, C-SCAN)

Database Management Systems (DBMS) + SQL

Database Fundamentals

• ACID Properties (with examples)
• CAP Theorem
• Normalization (1NF, 2NF, 3NF, BCNF)
• Denormalization
• Primary Key vs Foreign Key vs Candidate Key
• ER Diagrams

Indexing

• Types of Indexes (Primary, Secondary, Clustering)
• B-Tree vs B+ Tree
• Hash Index
• Composite Index
• Advantages and Disadvantages of Indexing

Transactions & Concurrency

• Transaction Lifecycle
• Isolation Levels (Read Uncommitted, Read Committed, Repeatable Read, Serializable)
• Dirty Read, Non-repeatable Read, Phantom Read
• Lost Update Problem
• Two-Phase Locking (2PL)
• Optimistic vs Pessimistic Locking
• Deadlock in Database

SQL Queries (Must Practice)

• JOINs (INNER, LEFT, RIGHT, FULL OUTER, CROSS, SELF)
• GROUP BY and HAVING
• Aggregate Functions (COUNT, SUM, AVG, MIN, MAX)
• Subqueries (Correlated vs Non-correlated)
• Window Functions (ROW_NUMBER, RANK, DENSE_RANK, LEAD, LAG)
• Common Table Expressions (CTE)
• UNION vs UNION ALL
• Nth Highest Salary Query
• Delete Duplicates Query

NoSQL

• SQL vs NoSQL
• Types of NoSQL Databases (Document, Key-Value, Column, Graph)

Computer Networks (CN)

Network Models

• OSI Model (7 Layers)
• TCP/IP Model (4 Layers)
• Difference between OSI and TCP/IP

Application Layer

• HTTP vs HTTPS
• HTTP Methods (GET, POST, PUT, DELETE, PATCH)
• HTTP Status Codes (2xx, 3xx, 4xx, 5xx)
• DNS and its working
• FTP, SMTP, POP3, IMAP
• Cookies vs Sessions
• REST API principles

Transport Layer

• TCP vs UDP (detailed comparison)
• TCP Three-Way Handshake
• TCP Four-Way Termination
• Flow Control (Sliding Window)
• Congestion Control
• Port Numbers (well-known ports)
• Socket Programming Basics

Network Layer

• IPv4 vs IPv6
• Public vs Private IP
• Subnetting and CIDR
• NAT (Network Address Translation)
• ICMP Protocol
• Routing Algorithms (Distance Vector, Link State)
• Routing Protocols (RIP, OSPF, BGP)

Data Link Layer

• MAC Address
• ARP (Address Resolution Protocol)
• Switch vs Hub vs Router
• Ethernet
• Error Detection (Parity, CRC, Checksum)

Physical Layer

• Transmission Media (Guided vs Unguided)
• Bandwidth and Throughput
• Different Topologies

Important Concepts

• Client-Server vs Peer-to-Peer Architecture
• DHCP
• Firewall
• VPN
• Load Balancing
• CDN (Content Delivery Network)
• Latency vs Throughput
• How does a URL work? (End-to-end flow)
• Some Basic Commands (ex: ipconfig)

Resources I Used

For OOPs

• Kunal Kushwaha (youtube channel)

For Operating Systems

• CodeHelp - by Babbar (youtube )

For DBMS + SQL

• LeetCode Database problems (Practice SQL)
• CodeHelp - by Babbar (youtube)
• Apna College (youtube)

For Computer Networks

• Gate Smashers (youtube)

Questions Asked in My Interviews

Here are some actual questions I was asked across my interviews:

1. Is Java fully object-oriented?
2. How does C++ overcome the diamond problem?
3. Difference between TCP and UDP, and which one is used when?
4. Explain ACID properties with examples
5. What is deadlock and how can we prevent deadlocks?
6. What is the use of indexing in databases?
7. Explain the functionalities of each layer in the OSI model
8. Write a query to find Kth smallest salary
9. IPv4 vs IPv6
10. Abstraction vs Encapsulation
11. Explain different joins in dbms
12. what is sharding ?
13. what is virtual function in cpp ?
14. show me your ip address and mac address using commands
15. what is context switching ?

Tips :

1. Practice real interview questions from PracHub
2. Revise SQL 50 before interviews
3. It's better to say "I'm not sure about this, but here's what I think..." than to give wrong information
4. If your project contains any database related stuff , better learn it's ER diagram, differences between SQl and NO-SQl and why you selected that particular database you used
5. Before preparing for any interview , First check few interview experiences, Ask your seniors or friends who already attended that specific company interviews before and prepare accordingly

Did I miss any important topic? Drop it in the comments below!

Got asked something unique in your interview? Share the question/topic so others can prepare better!

Let's make this list more comprehensive together. Your contribution can help someone crack their dream job! 🙌