PRACTICE QUESTION STRINGS

Duration: 2 min

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Inside: a video lesson and guided study material.

Module outline

  1. About Course: UPPSC Course Overview
  2. Interview Preparation & Guidance: Interview Preparation
  3. Paper 1 | General Hindi: भाषा, लिपि, ध्वनि, वर्ण, अक्षर, स्वर, व्यंजन, मात्रा और संयुक्ताक्षर, वर्तनी, वर्ण-विन्यास, अनुस्वार, अनुनासिक, चंद्रबिंदु और ‘र’ के रूप, शब्द, पद और शब्द-भेद, संज्ञा और सर्वनाम, विशेषण और क्रिया, लिंग, वचन, पुरुष और कारक, काल, वाच्य, वाक्य और वाक्य-भेद, वर्णमाला, समास, संधि, विलोम शब्द, पर्यायवाची शब्द, सामान्य अशुद्धियाँ, अनेक शब्दों के लिए एक शब्द, मुहावरे और लोकोक्तियाँ, अपठित गद्यांश और अपठित पद्यांश, Multi-Topic Content (Cross-Concept Material)
  4. Paper 2 | General Studies: State Wise GK, Polity, Geography, History, GK- Current Affairs
  5. Paper 1 | Programming Language: Language Design, C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, OOPS with C++
  6. Paper 1 | Database Management Systems: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, ORDBMS, NoSQL
  7. Paper 1 | Cyber Security: Society, Law & Ethics, Cyber Threats and Malware Attacks, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Electronic Data Interchange and E-Commerce, Physical Security and Cryptography Basics, Intrusion Detection Systems (IDS), Cyber Safety and Security, Ethical Hacking
  8. Paper 1 | Computer Organization and Architecture: Basics of COA, Programming the Basic Computer, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Register Transfer and Microoperations, Control Unit Design
  9. Paper 1 | Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
  10. Paper 1 | Design and Analysis of Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  11. Paper 1 | Data Structures: Introduction to DS, Array, Linked List, Stack, Queue, Tree, Graphs, Hashing
  12. Paper 1 | Discrete Structures and Theory of Logic: Permutation and Combination, Set Theory, Relations, Functions, Propositional and Predicate Logic, Graph Theory, Group Theory
  13. Paper 1 | Software Project Management: Software Project Management
  14. Paper 2 | Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Unix OS, Linux OS, Security
  15. Paper 2 | Compiler Design: Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment, Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Pushdown Automata & CFG, Complexity Theory
  16. Paper 2 | Artificial Intelligence & High Performance Computing: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Planning, Multi Agent Systems, Natural Language Processing, Emerging Tech Trends
  17. Paper 2 | Image Processing: Digital Image Fundamentals, Image Enhancement, Image Restoration, Color Image Processing, Image Compression
  18. Paper 2 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  19. Paper 2 | Computer Graphics: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing
  20. Paper 2 | Web Technologies: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, Emerging Technologies, HTML Basics, JavaScript-Basics, Java
  21. Paper 2 | Soft Computing: Fuzzy Sets, Artificial Neural Networks, Genetic Algorithms
  22. Paper 2 | Distributed System: Distributed Systems
  23. UPPSC Live Class Recordings: UPPSC Polytechnic Lecturer 2025 (CS)
  24. Previous Year Papers:
  25. Mock Test:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video features a lecture solving a multiple-choice question regarding the number of substrings of all lengths for a character string of length n. The question displays four options: a) n!, b) n^2, c) n(n-1)/2 - 1, and d) n(n+1)/2 + 1. The instructor highlights the phrase "substrings (of all lengths inclusive)" to clarify the problem scope. He uses the string "GATE" as a concrete example, noting its length is n=4. He systematically lists the substrings: single characters (G, A, T, E), pairs (GA, AT, TE), triplets (GAT, ATE), and the full string (GATE). He counts these to arrive at a total of 11. He then substitutes n=4 into the formulas for options (c) and (d). Option (c) results in 5, while option (d) results in 11. Since his manual count matches option (d), he selects it as the correct answer.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor begins by reading the question: "The number of substrings (of all lengths inclusive) that can be formed from a character string of length n is". He uses a red pen to circle the key terms "substrings" and "of all lengths inclusive" on the screen. To solve this, he writes the example string "GATE" on the digital whiteboard. He breaks down the substrings of "GATE" into groups based on their length: length 1 includes G, A, T, E; length 2 includes GA, AT, TE; length 3 includes GAT, ATE; and length 4 is GATE. He writes "n=4" to denote the length of the example string. He then proceeds to evaluate the given options by substituting n=4. He calculates the value for option (c) n(n-1)/2 - 1, writing "4(3)/2 - 1" which equals 5. He circles the result "5". Next, he evaluates option (d) n(n+1)/2 + 1, writing "4(5)/2 + 1" which equals 11. He writes "11" next to his list of substrings, indicating that he has counted 11 substrings in total.

  2. 2:00 – 2:09 02:00-02:09

    The instructor concludes the problem by finalizing his selection. He has circled the number "11" which corresponds to his manual count of substrings for the string "GATE". He then circles option (d) n(n+1)/2 + 1, confirming it as the correct formula based on the example. The final frame shows the circled option (d) and the calculated value 11, solidifying the connection between the example count and the algebraic expression.

The instructor demonstrates a problem-solving strategy for combinatorial string problems by using a concrete example to verify general formulas. By breaking down the string "GATE" into its constituent substrings and counting them to get 11, he establishes a baseline. He then validates this count against the provided algebraic options, finding that option (d) yields the same value (11) when n=4. This confirms option (d) as the correct answer in the context of this specific problem instance.

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