OOPS & Python Programming (4351108) - Summer 2024 Solution

Question 1(a) [3 marks]

Explain for loop working in Python.

Answer:

For loop repeats code block for each item in sequence like list, tuple, or string.

Syntax Table:

Diagram:

goat

• Iteration: Loop variable gets each value from sequence one by one
• Automatic: Python handles moving to next item automatically
• Flexible: Works with lists, strings, tuples, ranges

Mnemonic: "For Each Item, Execute Block"

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Question 1(b) [4 marks]

Explain working of if-elif-else in Python.

Answer:

Multi-way decision structure that checks multiple conditions in sequence.

Structure Table:

Flow Diagram:

goat

• Sequential: Checks conditions top to bottom
• Exclusive: Only one block executes
• Optional: elif and else are optional

Mnemonic: "If This, Else If That, Else Default"

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Question 1(c) [7 marks]

Explain structure of a Python Program.

Answer:

Python program has organized structure with specific components in logical order.

Program Structure Table:

Program Architecture:

goat

• Modular: Each section has specific purpose
• Readable: Clear organization helps understanding
• Maintainable: Easy to modify and debug
• Standard: Follows Python conventions

Simple Example:

Python

Mnemonic: "Comment, Import, Constant, Function, Class, Main"

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Question 1(c OR) [7 marks]

Explain features of Python Programming Language.

Answer:

Python has unique characteristics that make it popular for beginners and professionals.

Python Features Table:

Feature Categories:

goat

• Beginner-Friendly: Simple syntax like English language
• Versatile: Used for web, AI, data science, automation
• Rich Libraries: Huge collection of pre-built modules
• Dynamic Typing: No need to declare variable types
• Interactive: Can test code line by line in interpreter
• High-Level: Handles memory management automatically

Code Example:

Python

Mnemonic: "Simple, Interpreted, Object-Oriented, Open, Cross-platform"

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Question 2(a) [3 marks]

Explain any 3 operations done on Strings.

Answer:

String operations manipulate and process text data in various ways.

String Operations Table:

Operation Examples:

Python

• Concatenation: Joins two or more strings together
• Length: Counts total characters in string
• Case Conversion: Changes letter cases (upper/lower)

Mnemonic: "Combine, Count, Convert"

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Question 2(b) [4 marks]

Develop a Python program to convert temperature from Fahrenheit to Celsius unit using eq: C=(F-32)/1.8

Answer:

Program converts temperature using mathematical formula with user input.

Algorithm Table:

Complete Program:

Python

Test Cases:

• Input: 32°F → Output: 0.00°C

• Input: 100°F → Output: 37.78°C

• User Input: Gets Fahrenheit temperature from user

• Formula Application: Uses given conversion equation

• Formatted Output: Shows result with decimal places

Mnemonic: "Input, Calculate, Output"

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Question 2(c) [7 marks]

Explain in detail working of list data types in Python.

Answer:

List is ordered, mutable collection that stores multiple items in single variable.

List Characteristics Table:

List Operations Diagram:

goat

Common List Methods:

Example Code:

Python

• Dynamic Size: Can grow or shrink during execution
• Zero Indexing: First element at index 0
• Slicing: Can extract portions using [start:end]
• Nested Lists: Can contain other lists

Mnemonic: "Ordered, Mutable, Indexed, Mixed"

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Question 2(a OR) [3 marks]

Explain String formatting in Python.

Answer:

String formatting creates formatted strings by inserting values into templates.

Formatting Methods Table:

Example Usage:

Python

• Placeholder: marks where values go
• Dynamic: Values inserted at runtime
• Readable: Makes code cleaner than concatenation

Mnemonic: "Format, Insert, Display"

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Question 2(b OR) [4 marks]

Develop a Python program to identify whether the scanned number is even or odd and print an appropriate message.

Answer:

Program checks if number is divisible by 2 to determine even or odd.

Logic Table:

Complete Program:

Python

Test Cases:

• Input: 4 → Output: "4 is even"

• Input: 7 → Output: "7 is odd"

• Modulo Operator: % gives remainder after division

• Conditional Logic: if-else determines result

• User Feedback: Clear message about result

Mnemonic: "Input, Check Remainder, Display Result"

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Question 2(c OR) [7 marks]

Explain in detail working of Set data types in Python.

Answer:

Set is unordered collection of unique items with no duplicate values allowed.

Set Characteristics Table:

Set Operations Diagram:

goat

Set Methods Table:

Example Code:

Python

• Automatic Deduplication: Removes duplicate values automatically
• Fast Membership: Quick checking if item exists
• Mathematical Operations: Union, intersection, difference
• No Indexing: Cannot access items by position

Mnemonic: "Unique, Unordered, Mutable, Mathematical"

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Question 3(a) [3 marks]

Explain working of any 3 methods of math module.

Answer:

Math module provides mathematical functions for complex calculations.

Math Methods Table:

Usage Example:

Python

• Precision: More accurate than basic operators
• Import Required: Must import math module first
• Return Values: Usually return float numbers

Mnemonic: "Square root, Power, Ceiling"

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Question 3(b) [4 marks]

Develop a Python program to find sum of all elements in a list using for loop.

Answer:

Program iterates through list and accumulates sum of all elements.

Algorithm Table:

Complete Program:

Python

Test Case:

• Input: [1, 2, 3, 4, 5] → Output: 15

• Accumulator: Variable stores running total

• Iteration: Loop visits each element once

• Addition: Adds each element to running sum

Mnemonic: "Initialize, Loop, Add, Display"

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Question 3(c) [7 marks]

Develop a Python program to check if two lists are having similar length. If yes then merge them and create a dictionary from them.

Answer:

Program compares list lengths and creates dictionary if they match.

Logic Flow Table:

Process Diagram:

goat

Complete Program:

Python

Expected Output:

Dictionary created: {'name': 'John', 'age': 25, 'city': 'Mumbai'}

• Length Comparison: Ensures lists can be paired properly
• zip() Function: Pairs elements from both lists
• dict() Constructor: Creates dictionary from paired elements
• Error Handling: Prevents incorrect pairing

Alternative Method:

Python

Mnemonic: "Check Length, Zip, Create Dictionary"

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Question 3(a OR) [3 marks]

Explain working of any 3 methods of statistics module.

Answer:

Statistics module provides functions for statistical calculations on numeric data.

Statistics Methods Table:

Usage Example:

Python

• Data Analysis: Helps understand data patterns
• Built-in Functions: No need to write complex formulas
• Accurate Results: Handles edge cases properly

Mnemonic: "Mean, Median, Mode"

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Question 3(c OR) [7 marks]

Develop a Python program to count the number of times a character appears in a given string using a dictionary.

Answer:

Program creates dictionary where keys are characters and values are their counts.

Character Counting Algorithm:

Counting Process:

goat

Complete Program:

Python

Alternative Method (More Pythonic):

Python

Example Output:

Input: "hello"
Output: {'h': 1, 'e': 1, 'l': 2, 'o': 1}

• Dictionary Keys: Each unique character becomes a key
• Dictionary Values: Count of character occurrences
• get() Method: Returns 0 if key doesn't exist, avoiding errors
• Iteration: Processes each character in string once

Mnemonic: "Loop, Check, Count, Store"

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Question 4(a) [3 marks]

Explain working of Python class and objects with example.

Answer:

Class is blueprint for creating objects. Objects are instances of classes.

Class-Object Relationship:

Class Structure:

goat

Example Code:

Python

• Encapsulation: Groups related data and functions together
• Reusability: One class can create multiple objects
• Organization: Better code structure and maintenance

Mnemonic: "Class Blueprint, Object Instance"

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Question 4(b) [4 marks]

Develop a Python program to print all odd numbers in a list.

Answer:

Program filters list elements and displays only odd numbers.

Odd Number Check Table:

Complete Program:

Python

Alternative Methods:

Python

Expected Output:

Odd numbers in the list:
1 3 5 7 9

• Modulo Operation: % operator finds remainder
• Condition Check: If remainder is not 0, number is odd
• Loop Iteration: Checks each number in list

Mnemonic: "Loop, Check Remainder, Print Odd"

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Question 4(c) [7 marks]

Explain working of user defined functions in Python.

Answer:

User-defined functions are custom functions created by programmers to perform specific tasks.

Function Components Table:

Function Structure:

goat

Types of Functions:

Example Functions:

Python

Function Benefits:

• Reusability: Write once, use multiple times
• Modularity: Break complex problems into smaller parts
• Maintainability: Easy to update and debug
• Readability: Makes code more organized and understandable
• Testing: Can test individual functions separately

Variable Scope:

• Local Variables: Exist only inside function
• Global Variables: Accessible throughout program
• Parameters: Act as local variables

Mnemonic: "Define, Parameters, Body, Return"

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Question 4(a OR) [3 marks]

Explain working constructors in Python.

Answer:

Constructor is special method that initializes objects when they are created.

Constructor Details Table:

Constructor Example:

Python

• Automatic Execution: Runs immediately when object is created
• Initialization: Sets up object's initial state
• self Parameter: Refers to current object being created

Mnemonic: "Initialize, Automatic, Self"

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Question 4(b OR) [4 marks]

Develop a Python program to find smallest number in a list without using min function.

Answer:

Program manually compares all elements to find the smallest value.

Finding Minimum Algorithm:

Complete Program:

Python

Alternative Method:

Python

Expected Output:

Smallest number: 5

• Comparison Logic: Compare each element with current smallest
• Update Strategy: Replace smallest when smaller number found
• Linear Search: Check all elements once

Mnemonic: "Assume, Compare, Update, Display"

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Question 4(c OR) [7 marks]

Explain working of user defined Modules in Python.

Answer:

User-defined modules are custom Python files containing functions, classes, and variables that can be imported and used in other programs.

Module Components Table:

Module Creation Process:

goat

Example Module Creation:

File: math_operations.py

Python

Using the Module:

Import Methods Table:

Main Program:

Python

Module Benefits:

• Code Reusability: Write once, use in multiple programs
• Organization: Keep related functions together
• Namespace: Avoid naming conflicts
• Maintainability: Easy to update and debug
• Collaboration: Share modules with other developers

Module Search Path:

1. Current directory
2. PYTHONPATH environment variable
3. Standard library directories
4. Site-packages directory

Best Practices:

• Use descriptive module names
• Include docstrings for documentation
• Keep related functionality together
• Avoid circular imports

Mnemonic: "Create File, Define Functions, Import, Use"

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Question 5(a) [3 marks]

Explain single inheritance in Python with example.

Answer:

Single inheritance is when one class inherits properties and methods from exactly one parent class.

Inheritance Structure Table:

Inheritance Diagram:

goat

Example Code:

Python

• Code Reuse: Child class gets parent's functionality automatically
• Extension: Child can add new methods and attributes
• Is-a Relationship: Dog is-a Animal

Mnemonic: "One Parent, One Child"

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Question 5(b) [4 marks]

Explain concept of abstraction in Python with its advantages.

Answer:

Abstraction hides complex implementation details and shows only essential features to the user.

Abstraction Concepts Table:

Abstraction Implementation:

Python

Advantages Table:

• Hide Complexity: Users don't need to know internal workings
• Consistent Interface: All child classes follow same structure
• Force Implementation: Abstract methods must be defined in child classes

Mnemonic: "Hide Details, Show Interface"

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Question 5(c) [7 marks]

Develop a Python program to demonstrate working of multiple and multi-level inheritances.

Answer:

Program shows both inheritance types: multiple (multiple parents) and multi-level (chain of inheritance).

Inheritance Types Comparison:

Inheritance Hierarchy:

goat

Complete Program:

Python

Expected Output:

=== Multi-level Inheritance ===
Buddy can eat
Buddy breathes air
Buddy can bark

=== Multiple Inheritance ===
Method from Father class
Method from Mother class
Method from Child class

Child inherits from Father: True
Child inherits from Mother: True

Key Differences:

Method Resolution Order (MRO):

• Multiple: Python follows left-to-right order
• Multi-level: Goes up the inheritance chain

Mnemonic: "Multiple Parents, Multi-level Chain"

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Question 5(a OR) [3 marks]

Explain working of 3 types of methods in Python.

Answer:

Python classes have three types of methods based on how they access class data.

Method Types Table:

Example Code:

Python

• Instance Methods: Work with object-specific data using self
• Class Methods: Work with class-wide data using cls
• Static Methods: Independent utility functions

Mnemonic: "Instance Self, Class Cls, Static None"

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Question 5(b OR) [4 marks]

Explain polymorphism through inheritance in Python.

Answer:

Polymorphism allows objects of different classes to be treated as objects of common base class, with each implementing methods differently.

Polymorphism Concept Table:

Polymorphism Example:

Python

Benefits:

• Flexibility: Same code works with different object types
• Extensibility: Easy to add new classes without changing existing code
• Maintainability: Changes in one class don't affect others

Mnemonic: "Same Name, Different Behavior"

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Question 5(c OR) [7 marks]

Develop a Python program to demonstrate working of hybrid inheritance.

Answer:

Hybrid inheritance combines multiple and multi-level inheritance in single program structure.

Hybrid Inheritance Structure:

goat

Inheritance Types in Hybrid:

Complete Program:

Python

Expected Output:

=== Hybrid Inheritance Demo ===

--- Creating Hybrid Pet ---

--- Methods from Animal (Great-grandparent) ---
Buddy can eat
Buddy can sleep

--- Methods from Mammal (Grandparent) ---
Buddy breathes air
Buddy gives birth to babies

--- Methods from Dog (Parent 1) ---
Buddy barks: Woof!
Buddy is loyal to owner

--- Methods from Cat (Parent 2) ---
Buddy meows: Meow!
Buddy is independent

--- Own Methods ---
Buddy loves to play
Name: Buddy, Breed: Labrador-Persian Mix

--- Inheritance Chain ---
MRO (Method Resolution Order): (<class '__main__.HybridPet'>, <class '__main__.Dog'>, <class '__main__.Cat'>, <class '__main__.Mammal'>, <class '__main__.Animal'>, <class 'object'>)

Is HybridPet subclass of Animal? True
Is HybridPet subclass of Dog? True
Is HybridPet subclass of Cat? True

Key Features of Hybrid Inheritance:

• Complex Structure: Combines different inheritance types
• Method Resolution Order: Python follows specific order for method lookup
• Diamond Problem: Handled automatically by Python's MRO
• Flexibility: Access to methods from multiple parent classes

Advantages:

• Rich Functionality: Inherits from multiple sources
• Code Reuse: Maximum utilization of existing code
• Relationship Modeling: Represents complex real-world relationships

Challenges:

• Complexity: Harder to understand and maintain
• Name Conflicts: Multiple parents may have same method names
• Memory Usage: Objects carry more overhead

Mnemonic: "Hybrid Combines All Types"