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Data Structures and Algorithms → Introduction to DSA 35

Which keyword defines a class in Python?
class
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What is an object in Python OOP?
An instantiation of a class
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Which method is called automatically when an object is created?
__init__()
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What does 'self' represent in a Python class method?
Current instance of the class
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What is a class variable in Python?
Shared by all instances, defined outside constructor
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Which keyword makes a local variable refer to the global variable?
global
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Which type of method requires an object to be called?
Instance method
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Which decorator defines a class method?
@classmethod
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Which decorator defines a static method?
@staticmethod
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What parameter is the first argument in a class method?
cls
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What is a mutator (setter)?
Modifies value of instance variable
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How many types of inheritance are there in Python?
5
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In single inheritance, how many parent classes does a child have?
One
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Which inheritance has one child from two or more parents?
Multiple
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In multi-level inheritance, the structure is:
A child derived from another child class
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Which inheritance has two or more children from one parent?
Hierarchical
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What is hybrid inheritance?
Combination of more than one inheritance type
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What does polymorphism mean?
Multiple forms
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What is method overriding?
Child redefines parent's method
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Which module implements abstraction in Python?
abc
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What is an abstract method?
Has no implementation in base class
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What is an abstract class?
Class with at least one abstract method
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What does @property decorator do?
Access method as attribute without calling
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Which OOP concept hides unnecessary implementation details?
Abstraction
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Which OOP concept binds data and methods and restricts direct access?
Encapsulation
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Which is NOT a pillar of OOP?
Compilation
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What does __str__ method do?
Returns human-readable string of object
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What does __del__ method do?
Called when object is garbage collected
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What does super() do?
Calls parent class method from child
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Which relationship is represented by 'Dog IS-A Animal'?
Inheritance
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What prerequisite does binary search require?
Sorted list
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Binary search uses which algorithm technique?
Divide and conquer
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How is middle element calculated in binary search?
mid=(low+high)//2
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If search element > middle element, which half is searched?
Right half
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Time complexity of binary search?
O(log n)
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Data Structures and Algorithms → Searching Algorithms 5

What is linear search also called?
Sequential search
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Best case time complexity of linear search?
O(1)
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Worst case time complexity of linear search?
O(n)
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For what list size is linear search most suitable?
Smaller lists (<100)
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What does linear search return if element not found?
-1
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