SD

Question 1

What is a delegate in C#?

Answer 1

A delegate is a type that represents references to methods with a specific parameter list and return type.

Question 2

How can you declare a delegate in C#?

Answer 2

You can declare a delegate using the delegate keyword followed by the return type and parameters of the method it will reference.

Question 3

Can a delegate reference static methods?

Answer 3

Yes, a delegate can reference both instance methods and static methods.

Question 4

What is a multicast delegate in C#?

Answer 4

A multicast delegate is a delegate that holds references to multiple methods.

Question 5

How can you add methods to a multicast delegate in C#?

Answer 5

You can add methods to a multicast delegate using the += operator.

Question 6

What is the purpose of the Invoke method in C# delegates?

Answer 6

The Invoke method is used to call the methods that the delegate references.

Question 7

What is the difference between delegates and interfaces in C#?

Answer 7

Delegates are similar to interfaces but are used to create references to methods rather than defining a contract for classes.

Question 8

Can delegates be used for event handling in C#?

Answer 8

Yes, delegates are commonly used for event handling in C#.

Question 9

What is a callback in C#?

Answer 9

A callback is a method that is passed as an argument to another method and is called when a certain event occurs.

Question 10

How can you define a delegate with a custom signature in C#?

Answer 10

You can define a delegate with a custom signature by specifying the return type and parameters that the delegate will reference.

Question 11

Can delegates be used for asynchronous programming in C#?

Answer 11

Yes, delegates can be used for asynchronous programming in C# by using the BeginInvoke and EndInvoke methods.

Question 12

What is covariance in relation to delegates in C#?

Answer 12

Covariance allows you to assign a method that returns a more derived type to a delegate that returns a less derived type.

Question 13

What is contravariance in relation to delegates in C#?

Answer 13

Contravariance allows you to assign a method that accepts a less derived type as a parameter to a delegate that expects a more derived type.

Question 14

How can you check if a delegate is null in C#?

Answer 14

You can check if a delegate is null by comparing it to null or using the Equality operator.

Question 15

What is the difference between synchronous and asynchronous delegates in C#?

Answer 15

Synchronous delegates execute the methods immediately, while asynchronous delegates allow the methods to execute on a separate thread.

Question 16

How can you remove a method from a multicast delegate in C#?

Answer 16

You can remove a method from a multicast delegate using the -= operator.

Question 17

What is the purpose of the GetInvocationList method in C# delegates?

Answer 17

The GetInvocationList method returns an array of delegates that represent the methods currently referenced by a multicast delegate.

Question 18

Can delegates be used with lambda expressions in C#?

Answer 18

Yes, delegates can be used with lambda expressions to create inline methods.

Question 19

What is the difference between a delegate and an event in C#?

Answer 19

An event is a special type of delegate that can only be invoked from within the class that defines it.

Question 20

How can you create a generic delegate in C#?

Answer 20

You can create a generic delegate by using the generic type parameters when declaring the delegate.

Question 21

What is the purpose of the DynamicInvoke method in C# delegates?

Answer 21

The DynamicInvoke method is used to invoke the methods that the delegate references with parameters passed as an object array.

Question 22

Can delegates be used with anonymous methods in C#?

Answer 22

Yes, delegates can be used with anonymous methods to define inline methods without a separate method declaration.

Question 23

What is the difference between a delegate and a function pointer?

Answer 23

Function pointers are a feature of C and C++, while delegates are a type-safe object-oriented way to refer to methods in C#.

Question 24

How can you pass a delegate as a parameter in C#?

Answer 24

You can pass a delegate as a parameter by declaring the parameter as the delegate type that the method expects.

Question 25

What are the built-in types available in Python?

Answer 25

Common immutable types:
* numbers: int(), float(), complex()
* immutable sequences: str(), tuple(), frozenset(), bytes()
Common mutable types:
* mutable sequences: list(), bytearray()
* set type: set()
* mapping type: dict()
* classes, class instances
* etc.

Question 26

What is a characteristic of Python regarding variable types?

Answer 26

Python is dynamically typed, meaning you don’t need to state the types of variables when declaring them.

Question 27

What does it mean that functions are first-class objects in Python?

Answer 27

Functions can be assigned to variables, returned from other functions, and passed into functions.

Question 28

How do you modify a string in Python?

Answer 28

You can’t modify a string directly because they are immutable. Instead, construct a new string from parts.

Question 29

What are some benefits of using Python?

Answer 29

Benefits include:
* Dynamic typing
* Support for object-oriented programming
* Functions as first-class objects
* Quick development
* Versatile usage in various fields

Question 30

What is a Lambda Function in Python?

Answer 30

A small anonymous function that can take any number of arguments but has only one expression.

Question 31

When would you use a tuple instead of a list in Python?

Answer 31

Use a tuple to store a sequence of items that will not change.

Question 32

What is a negative index in Python?

Answer 32

Negative indices count from the right, with list[-1] referring to the last element.

Question 33

Define global variables in Python.

Answer 33

Variables declared outside a function or in global space that can be accessed by any function.

Question 34

Define local variables in Python.

Answer 34

Variables declared inside a function that are only accessible within that function.

Question 35

What is the rule regarding local and global variables in Python?

Answer 35

In Python, variables are local unless explicitly declared as global.

Question 36

Does Python have a switch-case statement?

Answer 36

No, before Python 3.10, Python did not have a switch-case statement; it can be simulated using if-elif-else.

Question 37

How can you convert a string to a number in Python?

Answer 37

Use built-in functions like int() and float(). For example: int(‘1’) == 1.

Question 38

What are descriptors in Python?

Answer 38

Descriptors allow adding managed attributes to objects through methods __get__, __set__, and __delete__.

Question 39

What is Linear (Sequential) Search?

Answer 39

A method that checks each element in an array for a match, with a time complexity of O(n).

Question 40

When would you use Linear Search?

Answer 40

When the array is small, you cannot rearrange elements, or when you have no idea what you’re searching for.

Question 41

What is the purpose of the pass statement in Python?

Answer 41

To create empty code blocks where Python requires a statement.

Question 42

What is the difference between lists and tuples?

Answer 42

Tuples are immutable, meaning their values cannot change, while lists are mutable.

Question 43

Is it possible to have static methods in Python?

Answer 43

Yes, using the @staticmethod decorator.

Question 44

How does Python memory management work?

Answer 44

Python uses garbage collection to manage memory, automatically freeing objects no longer referenced.

Question 45

What is the difference between the list methods append() and extend()?

Answer 45

append() adds an element as a single item, while extend() concatenates another iterable to the list.

Question 46

What is a Jump (or Block) Search?

Question 47

What does the ‘extend’ method do in Python?

Answer 47

Concatenates the first list with another list (or another iterable, not necessarily a list).

Question 48

What is Jump Search?

Answer 48

An algorithm used to search for the position of a target element on a sorted data collection or structure.

Question 49

How does Jump Search improve over Linear Search?

Answer 49

By skipping some fixed number of elements in every iteration.

Question 50

In Jump Search, what is the role of the variable ‘m’?

Answer 50

It represents the size of the block that can be skipped in every iteration.

Question 51

What is the time complexity of Jump Search?

Answer 51

O(√n)

Question 52

What is the space complexity of Jump Search?

Answer 52

O(1)

Question 53

What is the key advantage of Jump Search compared to Binary Search?

Answer 53

It does not rely on the division operator (/).

Question 54

True or False: Jump Search performs a linear search after identifying the block that may contain the target element.

Answer 54

True

Question 55

What is Interpolation Search?

Answer 55

An algorithm similar to Binary Search that improves search efficiency for uniformly distributed values in a sorted array.

Question 56

How does Interpolation Search differ from Binary Search?

Answer 56

It calculates the estimated position of the target value based on the values of the array.

Question 57

What is the formula used in Interpolation Search to find the position?

Answer 57

pos = low + [(x - arr[low]) * (hi - low) / (arr[hi] - arr[low])]

Question 58

What is the average case time complexity of Interpolation Search?

Answer 58

O(log log n)

Question 59

What is the worst-case time complexity of Interpolation Search?

Answer 59

O(n)

Question 60

Fill in the blank: Jump Search maintains a worst and average case efficiency of O(_______) complexity.

Answer 60

√n

Question 61

What is the optimal block size for Jump Search?

Answer 61

√n

Question 62

True or False: Interpolation Search is more efficient than Binary Search when values are uniformly distributed.

Answer 62

True