Mastering Python Loops

What is the syntax for a basic for loop in Python?

• for variable in sequence:

• for variable in (sequence)

• for (variable : sequence)

• foreach variable in sequence:

How does a while loop differ from a for loop?

• A for loop can only iterate over arrays, while a while loop can iterate over any data type.

• A while loop checks a condition before each iteration, while a for loop is used for a known number of iterations with initialization, condition, and increment in one line.

• A while loop is always faster than a for loop.

• A while loop requires a counter variable, while a for loop does not.

What will be the output of the following code: for i in range(3): print(i)?

• 3

• 0 1 2

• -1

• 1.5

Explain the purpose of the break statement in loops.

• The break statement is used to skip the current loop iteration.

• The break statement continues to the next iteration of the loop.

• The break statement pauses the loop for a specified time.

• The purpose of the break statement in loops is to exit the loop prematurely.

What is the output of the following code: while True: print('Hello')?

• The output is 'Hello' printed once.

• The output is an error message.

• The output is 'Hello' printed indefinitely.

• The output is 'Hello' printed with a delay.

How can you loop through a list in Python?

• Use a while loop: while item in list: print(item)

• Use a for loop: for item in list: print(item)

• Iterate using list comprehension: [print(item) for item in list]

• Access elements by index: for i in range(len(list)): print(list[i])

What is a nested loop and when would you use it?

• A nested loop is used to create single-dimensional arrays.

• Nested loops are only applicable in object-oriented programming.

• You should avoid using nested loops as they are inefficient for all tasks.

• A nested loop is used when you need to iterate over multi-dimensional data or perform operations that involve combinations of multiple sets.

What does the continue statement do in a loop?

• The continue statement pauses the loop for a specified time.

• The continue statement ends the loop immediately.

• The continue statement skips the current iteration of a loop.

• The continue statement restarts the loop from the beginning.

How can you iterate over a dictionary in Python?

• for dict in keys():

• for key in dict.keys()

• Use 'for key in dict:', 'for value in dict.values()', or 'for key, value in dict.items()'.

• for item in dict:

What is the result of using a for loop with the zip function?

• The result is a single list of all elements combined.

• The result is an error due to incompatible input types.

• The result is an iterable of tuples, where each tuple contains elements from the input iterables.

• The result is a dictionary mapping the first iterable to the second.