Mettl Fundamental Coding Skills 2

Question 1

What is the time complexity of accessing an element in an array by index?

Accepted Answer

O(1)

Answer

Array index access is O(1) because the memory address is computed directly from the base address and index.

Question 2

Which of the following correctly declares a constant in JavaScript?

Accepted Answer

const PI = 3.14;

Answer

The `const` keyword declares a block-scoped constant that cannot be reassigned after initialization.

Question 3

What does the modulo operator (%) return?

Accepted Answer

The remainder after division

Answer

The modulo operator returns the remainder when the left operand is divided by the right operand.

Question 4

Which data structure follows the LIFO (Last In, First Out) principle?

Accepted Answer

Stack

Answer

A stack is a LIFO structure where the last element pushed is the first one popped.

Question 5

What will `print(type([]))` output in Python?

Accepted Answer

Answer

Square brackets `[]` create a list in Python, so `type([])` returns `<class 'list'>`.

Mettl Practice Test