Mettl Coding Skills 2

Question 1

What will the following Python code output?

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

Accepted Answer

[2, 3, 4]

Answer

Python slicing x[1:4] returns elements at indices 1, 2, 3 (not including index 4): x[1]=2, x[2]=3, x[3]=4. Result: [2, 3, 4].

Question 2

What is the time complexity of binary search?

Accepted Answer

O(log n)

Answer

Binary search halves the search space with each comparison, giving O(log n) time complexity.

Question 3

Which SQL statement is used to retrieve unique values from a column?

Accepted Answer

SELECT DISTINCT

Answer

SELECT DISTINCT eliminates duplicate rows from the result set.

Question 4

In object-oriented programming, what is 'encapsulation'?

Accepted Answer

Bundling data and methods into a single unit and restricting access

Answer

Encapsulation bundles data (attributes) and the methods that operate on that data into a single unit (class) and controls access through access modifiers.

Question 5

What does the following pseudocode return for input n=5?

function factorial(n):
  if n == 0: return 1
  return n * factorial(n-1)

Accepted Answer

120

Answer

factorial(5) = 5 × factorial(4) = 5 × 4 × 3 × 2 × 1 = 120.

Mettl Practice Test

Mettl Practice Test

Mettl Coding Skills 2