Data Structures, Java, Python, Excel

1. Data Structures

• Basics
• Definition, Types (Linear vs Non-Linear)
• Time & Space Complexity (Big-O Notation)
• Linear Data Structures
• Arrays (1D, 2D, Operations, Searching, Sorting)
• Linked List (Singly, Doubly, Circular)
• Stack (Operations, Applications: expression evaluation, undo/redo)
• Queue (Simple, Circular, Priority, Deque)
• Non-Linear Data Structures
• Trees (Binary Tree, BST, AVL, Heap, B-Trees)
• Graphs (Representation, BFS, DFS, Dijkstra, MST)
• Hashing
• Hash Functions, Collisions (Chaining, Open Addressing)
• Advanced
• Tries, Segment Trees, Disjoint Sets

2. Java

• Core Java
• Data Types, Variables, Operators
• Control Statements (if, switch, loops)
• OOP Concepts (Class, Object, Inheritance, Polymorphism, Abstraction, Encapsulation)
• Exception Handling
• Collections Framework (List, Set, Map, Queue)
• Advanced Java
• Multithreading & Concurrency
• JDBC (Database Connectivity)
• Streams & Lambda Expressions
• File Handling
• Interview Focus
• Garbage Collection
• Memory Management (Heap vs Stack)
• Java 8 Features

3. Python

• Basics
• Data Types, Variables, Operators
• Control Flow (if, for, while)
• Functions & Recursion
• Exception Handling
• Intermediate
• Lists, Tuples, Sets, Dictionaries
• String Handling
• File Handling
• Modules & Packages
• Advanced
• OOP in Python (Classes, Inheritance, Polymorphism)
• Iterators & Generators
• Decorators
• Libraries (NumPy, Pandas, Matplotlib for Data Analytics)
• Practical
• Data Analysis in Python (Excel, CSV, SQL Integration)

4. Excel

• Basics
• Data Entry, Formatting, Shortcuts
• Formulas & Functions (SUM, AVERAGE, COUNT, IF, VLOOKUP, HLOOKUP, INDEX-MATCH)
• Intermediate
• Conditional Formatting
• Data Validation & Dropdowns
• Pivot Tables & Pivot Charts
• Advanced
• Macros & VBA Basics
• What-If Analysis (Goal Seek, Scenario Manager)
• Power Query & Power Pivot
• Data Analytics with Excel
• Cleaning Data
• Dashboard Creation
• Connecting Excel with SQL / Python