CBSE Class 11 Computer Science: Chapters 1-8 Fundamentals (卷

Volume 1: Programming First Strategy PART 1

Chapters 1-8: Computational Thinking to Modules Strictly from Textbook - Detailed Concepts, Programs & Exercises

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• 1. Computational Thinking & Programming – I
• 2. Python Basics (Tokens, Identifiers, Variables, Data Types, Operators)
• 3. Flow of Control
• 4. Strings
• 5. Lists
• 6. Tuples
• 7. Dictionary
• 8. Modules

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1

Computational Thinking & Programming – I

Problem-Solving Using Algorithms and Computational Steps

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> Computational thinking refers to the thought processes involved in formulating problems so their solutions can be represented as computational steps and algorithms. In education, computational thinking is a set of problem-solving methods that involve expressing problems and their solutions in ways that a computer could also execute.

— Wikipedia: Computational Thinking

• Simple Meaning: Thought processes to turn problems into computer-executable steps
• Hinglish (Devanshu Sir): "Bhai, problem ko algorithm steps mein convert karna jaise daily routine plan!"
• Real Life Example: Planning a school project - divide tasks, assign, sequence
• Step-by-Step Explanation:

1. Identify problem
2. Decompose into parts
3. Recognize patterns
4. Abstract details
5. Create algorithm

• Analogy: Building a puzzle - sort pieces, connect logically
• Exam Tip: Always link to 4 pillars: Decomposition, Pattern Recognition, Abstraction, Algorithms
• Memory Trick: "DPAA" - Decompose, Pattern, Abstract, Algorithm

• Decomposition: Break complex problem into smaller parts
• Pattern Recognition: Find similarities in problems
• Abstraction: Focus on important details, ignore irrelevant
• Algorithm Design: Create step-by-step solution

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Traditional Problem Solving

• Manual calculations
• Limited to human speed
• Error-prone for complex tasks
• Step-by-step on paper

Computational Thinking

• Automated via algorithms
• Handles massive data
• Precise & repeatable
• Scalable for big problems
• Uses computers for execution

> The maths taught around the world today does not fit how it is used in the real world. Computation technology is more accessible than ever before, but no curriculum in the world assumes it exists. Instead, it is focussed on the mechanics of hand calculation, rather than the essence of real-world maths.

— Conrad Wolfram (Advocate of Computational Literacy)

• Simple Meaning: Step-by-step procedure to solve a problem
• Hinglish: "Recipe jaise, har step clear!"
• Real Life: Making tea - boil water, add tea, sugar, milk, serve
• Step-by-Step: Finite, unambiguous, input/output defined, effective
• Analogy: GPS directions - turn left, go straight 2km
• Exam Tip: Characteristics: Finiteness, Definiteness, Input, Output, Effectiveness
• Memory Trick: "FIDOE" - Finite, Input, Definite, Output, Effective

• Start → Input a,b → Decision a>b? → Yes: Print a → No: Print b → Stop
• Symbols: Oval=Start/Stop, Parallelogram=Input, Diamond=Decision, Rectangle=Process
• Exam Tip: Practice drawing flowcharts for all programs

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a = int(input("Enter first number: "))b = int(input("Enter second number: "))if a > b:    print(a, "is larger")else:    print(b, "is larger")

• Sample Input:

Enter first: 20 Enter second: 15

• Sample Output: 20 is larger
• Common Mistakes: 1. No int() - TypeError 2. Wrong indentation
• Practice Task: Modify for three numbers

• 1. What is computational thinking? a) Math only b) Problem-solving for computers c) Gaming d) Drawing
• 2. Key pillars include: a) Decomposition b) Swimming c) Eating d) Sleeping
• 3. Algorithm must be: a) Infinite b) Ambiguous c) Finite & Definite d) Random
• 4. Flowchart diamond shape: a) Input b) Decision c) Process d) Start
• 5. Memory trick for algorithm: a) ABC b) FIDOE c) XYZ d) 123

• 1. Define Computational Thinking with 2 examples.
• 2. List 4 characteristics of an algorithm.
• 3. Differentiate Algorithm and Program.
• 4. Draw flowchart symbols for Decision and Input.
• 5. Explain Decomposition with real-life example.

• 1. Explain 4 pillars of Computational Thinking with examples and flowchart for sum of two numbers.
• 2. Write algorithm, flowchart and Python program to check even/odd number. Include dry run.

• 1. thinking is solving problems like a computer.
• 2. Step-by-step solution is called .
• 3. Breaking problem into parts:
• 4. Visual algorithm representation:
• 5. Algorithm must terminate: _ ness

• 1. Computational Thinking helps in automation. (T/F)
• 2. Algorithms can be infinite loops. (T/F)
• 3. Flowcharts use standard symbols. (T/F)
• 4. Programs are written in English only. (T/F)
• 5. Abstraction ignores unnecessary details. (T/F)

• Task: Write Python program to input name and age, print 'Hello [name], you are [age] years old.'
• Requirements: Use input(), print(). Test with 2 inputs.
• Extension: Add if age>18 print 'Adult' else 'Minor'

• Project: Simple Calculator Algorithm & Program
• Steps: 1. Algorithm 2. Flowchart 3. Python code for +,-,*,/ 4. Dry run table
• Input two numbers and operation, output result
• Use if-elif for operations
• Bonus: Error handling for /0