Python List & Tuple MCQs

Question 11: What will be the output of the following code?

x = [x for x in range(10) if x <5] print(x)

Answer: D

Above, [x for x in range(10) if x<5] returns a new list using the list comprehension. First, it executes the for loop for x in range(10). The element x will be returned if the specified condition if x<5 evaluates to True. If the condition evaluates to True, then the expression before for loop would be executed and stored in the new list. Here, expression x simply stores the value of x into a new list.

Question 12: What will be the output of the following code?

lst = [1, 2, 3, 4, 5]
del lst[:]
print(lst)

Answer: B

Question 13: What will be the output of the following code?

lst = [1, 2, 3, 4, 5]
print(lst[0:1]

Answer: B

lst[0:1] returns 1 element from 0 index.

The range slice operator [FromIndex : Untill Index - 1] fetches items in the range specified by the two index operands separated by : symbol. If the first operand is omitted, the range starts from the index 0. If the second operand is omitted, the range goes up to the end of the list. Visit list operators for more information.

Question 14: What will be the output of the following code?

lst = [1, 2, 3, 4, 5]
print(lst[-5:-3])

Answer: A

lst[-5,-3] returns two elements from -5 index until -3. List supports negative indexing where the first element's negative index = -(total number of element). Above, -5 index returns 1 and -3 index returns 3.

The range slice operator [FromIndex : Untill Index - 1] fetches items in the range specified by the two index operands separated by : symbol. If the first operand is omitted, the range starts from the index 0. If the second operand is omitted, the range goes up to the end of the list. Visit list operators for more information.

Question 15: What will be the output of the following code?

lst = [1, 2, 3]
lst[:]=[4,5,6]
print(lst)

Answer: B

lst[:]=[4,5,6] replaces all the elements of the list.