Python quiz

More questions about Python

These visible examples show the question style. LearnClash turns the full topic into ranked duels and spaced repetition.

1. 1 Medium

   Which Python collection gives the fastest appends at both ends?

   Answer: deque

   Why: Inserting at the front of a list requires shifting every element in O(n) time, whereas a deque does it in O(1).

2. 2 Easy

   What index number retrieves the very first element of a Python list?

   Answer: 0

   Why: Negative indexing is also supported, where index -1 accesses the very last element of the list.

3. 3 Medium

   When does the else block of a Python for loop execute?

   Answer: If no break statement was triggered

   Why: This pattern eliminates the need for boolean flag variables when searching through sequences for a target item.

4. 4 Easy

   What fundamental property distinguishes a Python tuple from a standard list?

   Answer: Immutability

   Why: Tuples containing only immutable elements can serve as dictionary keys, while lists can never be hashed as keys.

5. 5 Easy

   Which keyword is used to define a new function?

   Answer: def

   Why: Short for 'define', def binds a function object to a specified name in local scope.

6. 6 Easy

   What symbol marks the start of a single-line comment?

   Answer: #

   Why: One Python comment is not ignored: a '# coding:' line on line 1 or 2 sets the file's encoding, and without it Python 3 assumes UTF-8.