Cognizant Cognizant Data Structures and Algorithms

Question 1

What is the time complexity of binary search on a sorted array of n elements?

Accepted Answer

O(log n)

Answer

O(n)

Answer

O(n log n)

Answer

O(1)

Question 2

Which data structure uses LIFO (Last In, First Out) order?

Accepted Answer

Stack

Answer

Queue

Answer

Linked List

Answer

Heap

Question 3

What is the worst-case time complexity of QuickSort?

Accepted Answer

O(n²)

Answer

O(n log n)

Answer

O(log n)

Answer

O(n)

Question 4

Which traversal of a Binary Search Tree produces elements in sorted order?

Accepted Answer

In-order

Answer

Pre-order

Answer

Post-order

Answer

Level-order

Question 5

What data structure is best suited for implementing a BFS (Breadth-First Search)?

Accepted Answer

Queue

Answer

Stack

Answer

Priority Queue

Answer

Hash Map

Question 6

What is the space complexity of a recursive function that calls itself n times without tail-call optimization?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(log n)

Answer

O(n²)