Demo: Reverse Alphabet to Number Mapping

Duration: 10 min

This video lesson is available to enrolled students.

Return to /learn/BIHAR-STET-COMPUTER-SCIENCE-COMPLETE-COURSE/logical-reasoning/coding-decoding/basic-concepts-alphabetnumber-mapping-and-base-conversions/asset-demo-reverse-alphabet-to-number-mapping after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. About the course: About the Course
  2. Mathematical Aptitude: संख्या पद्धति / Number System, महत्तम समापवर्तक और लघुत्तम समापवर्त्य / HCF and LCM, Divisibility Rules, प्रतिशत / Percentage, अनुपात और समानुपात / Ratio and Proportion, औसत / Average, लाभ, हानि और बट्टा / Profit, Loss and Discount, समय और कार्य / Time and Work, घन क्षेत्रमिति / Solid Mensuration, साधारण और चक्रवृद्धि ब्याज / Simple and Compound Interest, समय, चाल और दूरी / Time, Speed and Distance, Age Problems, मिश्रण और एलिगेशन / Mixture and Alligation, Algebra, सरलीकरण, घातांक और करणी / Simplification, Indices and Surds, Pipe and Cistern, Trigonometry, Statistics, आँकड़ा निर्वचन / Data Interpretation, Arithmetic, समुच्चय, संबंध, फलन और विविक्त गणित / Sets, Relations, Functions and Discrete Mathematics, संख्या पद्धति और संख्या सिद्धांत / Number Systems and Number Theory, निर्देशांक ज्यामिति, सदिश और त्रिविमीय ज्यामिति / Coordinate Geometry, Vectors and 3D Geometry, बहुपद, समीकरण और सम्मिश्र संख्याएँ / Polynomials, Equations and Complex Numbers
  3. Logical Reasoning: श्रेणी / Series, कूट लेखन एवं कूट वाचन / Coding-Decoding, सादृश्यता एवं वर्गीकरण / Analogy and Classification, रक्त संबंध / Blood Relations, दिशा एवं दूरी / Direction and Distance, क्रम एवं रैंकिंग / Order and Ranking, अशाब्दिक तर्क / Non-Verbal Reasoning, बैठक व्यवस्था एवं पहेलियाँ / Seating Arrangement and Puzzles, Syllogisms, वेन आरेख, न्याय वाक्य एवं असमानता / Venn Diagrams, Syllogism and Inequalities, गणितीय संक्रियाएँ एवं लुप्त संख्या / Mathematical Operations and Missing Numbers, वर्णमाला एवं संख्या परीक्षण / Alphabet and Number Test, कथन आधारित तार्किक विवेचन / Statement-Based Reasoning, Analytical Reasoning (Counting Figures Reasoning), घन, पासा एवं आकृतियों की गिनती / Cubes, Dice and Figure Counting, कैलेंडर एवं घड़ी / Calendar and Clock, Clock
  4. General Knowledge: वैज्ञानिक उपलब्धियाँ और अनुसंधान / Scientific Achievements and Research, Chemistry, Biology, History, Geography, Polity, Indian Economy, समसामयिकी / Current Affairs, Static General Knowledge
  5. Art of Teaching: शिक्षण-अधिगम प्रक्रिया एवं कक्षा प्रबंधन / Teaching-Learning Process and Classroom Management, Learners & Learning Process, Factors Affecting Teaching, शिक्षण विधियाँ एवं उपागम / Teaching Methods and Approaches, सूक्ष्म शिक्षण एवं कक्षा संप्रेषण / Microteaching and Classroom Communication, शिक्षण सहायक सामग्री एवं शैक्षिक तकनीकी / Teaching Aids and Educational Technology, आकलन एवं मूल्यांकन / Assessment and Evaluation, शिक्षक: गुण, व्यावसायिक नैतिकता एवं विकास / Teacher: Qualities, Professional Ethics and Development, शैक्षिक नीतियाँ, अधिनियम एवं प्रशासन / Educational Policies, Acts and Administration, पाठ्यचर्या, कला एवं सह-शैक्षिक क्षेत्र / Curriculum, Arts and Co-curricular Areas, निर्देशन एवं परामर्श / Guidance and Counselling, दिव्यांग बच्चों की शिक्षा / Education of Children with Disabilities, Micro-Teaching & Teaching Skills, पाठ योजना / Lesson Planning
  6. Environmental Science: Environment
  7. Unit 1 | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  8. Unit 2 | COA: Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Programming the Basic Computer
  9. Unit 3 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  10. Unit 3 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  11. Unit 4 | Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  12. Unit 5 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management
  13. Unit 6 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control
  14. Unit 7 | 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
  15. Unit 8 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  16. Unit 9 | Object Oriented Programming: OOPS with C++
  17. Unit 10 | Web Development: HTML Basics, CSS, JavaScript-Basics, XML, Node.js
  18. Unit 11 | Theory Of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines
  19. Unit 12 | IoT: Emerging Tech Trends, Cloud Computing, कंप्यूटर नेटवर्क / Computer Networks
  20. Unit 13 | Artificial Intelligence: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Natural Language Processing, Artificial Neural Networks, Genetic Algorithms
  21. Unit 14 | E-Commerce: Electronic Data Interchange and E-Commerce, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Physical Security and Cryptography Basics, Cyber Safety and Security
  22. Unit 15 | Multimedia: Multimedia
  23. Unit 16 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
  24. Full Length Mock Tests — General Paper:
  25. Full Length Mock Tests — Computer Science (Paper II):
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video introduces a reverse alphabet-to-number mapping technique designed to solve coding and decoding problems. The instructor establishes the foundational concept by presenting a visual chart that pairs standard alphabet sequences with their reverse counterparts, specifically highlighting how letters from A to M correspond to Z to N. The core mathematical principle is defined as L + C = 27, where 'L' represents the position of a letter in the standard alphabet and 'C' represents its conjugate or reverse counterpart. This relationship is demonstrated through specific examples, such as the letter 'G' mapping to 'T', and 'T' (position 20) mapping to 'G' (position 7), confirming that their sum equals 27. The lesson progresses to a grid-based visual aid where letters are assigned numbers based on their position from the end of the alphabet, with Z=1 and A=26. This grid facilitates quick lookup for reverse mappings, allowing students to convert letters into numerical values efficiently.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video begins by introducing the concept of 'Letter to Reverse Number Mapping' using a visual chart that pairs standard alphabet sequences with their reverse counterparts. The instructor highlights the letter 'G' to demonstrate how a specific position in the forward alphabet corresponds to a reversed sequence. This visual aid serves as a foundational tool for solving coding and decoding problems by establishing the relationship between forward and backward letter positions. On-screen text displays 'Letter to Reverse Number Mapping' alongside the standard alphabet A-M and its reverse Z-N, reinforcing the visual pairing of letters like G with T. The instructor circles specific letters to emphasize the mapping relationship, setting the stage for mathematical derivations.

  2. 2:00 – 5:00 02:00-05:00

    The instructor demonstrates a 'Letter to Reverse Number Mapping' technique using two sets of alphabets, highlighting pairs like G and T to show their correspondence in a reverse sequence. A mathematical formula L + C = 27 is introduced, where 'conjugate' refers to the sum of a letter's position and its reverse counterpart. The visual aids include circled letters and handwritten notes explaining the relationship between forward and backward alphabet positions. Specific calculations are shown, such as T (20) mapping to G (7), confirming the sum of 27. The lesson transitions to a grid-based visual aid where letters are arranged in reverse order (Z=1, Y=2, etc.) to facilitate quick lookup of these mappings. Key terms like 'conjugate' are labeled on screen, and the instructor circles letters K and P to demonstrate their mapped numbers 11 and 16 respectively.

  3. 5:00 – 10:00 05:00-10:00

    The video segment focuses on a mnemonic story involving a character named Aziz to teach reverse alphabet mapping. The instructor highlights specific words like 'BOY', 'FALTU', and 'GREAT' while underlining them to emphasize their role in the memory aid. The story progresses through Aziz's actions, his father's reaction, and his marriage to a 'JUNGLE QUEEN', linking these narrative elements to the alphabet sequence. The instructor demonstrates how to apply the reverse mapping technique to solve word-based problems, such as finding the value for 'JUNGLE QUEEN' by summing individual letter values. A reverse alphabet grid is displayed with Z=1 to A=26, and specific letter values like O=12 and A=26 are circled. The lesson concludes with the application of this mapping to solve word problems, showing calculations for words like 'KURTA PYJAMA' and 'LOTTO shoes', ultimately deriving a single digit answer (SA) from the sum of mapped numbers.

  4. 10:00 – 10:02 10:00-10:02

    The video displays a text-based story problem involving a character named Aziz and his activities, alongside an alphabet chart. The educational focus appears to be on mapping letters to numbers or identifying specific words within the text, as suggested by the 'Reverse Alphabet to Number Mapping' asset title. The story details Aziz's actions, his marriage, and his attire, with specific words highlighted in red for emphasis. The on-screen text presents the full narrative about Aziz's exam day, his movie watching, and his marriage to a 'JUNGLE QUEEN', providing the context for applying the reverse mapping rules discussed throughout the lesson.

The video provides a comprehensive guide to reverse alphabet-to-number mapping, a technique essential for coding and decoding problems in competitive exams. The core concept relies on the mathematical relationship L + C = 27, where a letter's position in the standard alphabet plus its reverse counterpart equals 27. This principle is visually reinforced through charts pairing A-M with Z-N and grids assigning values from Z=1 to A=26. The instructor uses specific examples like 'G' mapping to 'T' and 'K' mapping to 11 to illustrate the method. A mnemonic story about a character named Aziz serves as a memory aid, linking narrative elements like 'BOY', 'FALTU', and 'JUNGLE QUEEN' to the alphabet sequence. The lesson culminates in applying these mappings to solve word-based problems, such as calculating the sum of values for 'JUNGLE QUEEN' or deriving a single digit answer from mapped numbers. The visual aids, including circled letters and handwritten notes, ensure that students can easily follow the step-by-step process of converting letters to numbers using reverse alphabetical order.

Loading lesson…