Data Structures, Algorithms, Programming Concepts (C/C++/Python/Java), OOP & Web Development (Part 6)

Question 1

In an array-based Circular Queue of size $N$, what mathematical pointer arithmetic formula is used to advance the `rear` index during an `enqueue()` operation?

Accepted Answer

rear = (rear + 1) mod N

Answer

rear = rear + 1

Answer

rear = (rear + N) / 2

Answer

rear = rear - 1

Question 2

What is a "Deque" (Double-Ended Queue)?

Accepted Answer

A linear data structure where elements can be inserted and deleted from BOTH the front and the rear ends

Answer

A queue that holds only double-precision floating-point numbers

Answer

A queue with two separate physical CPU connections

Answer

A queue that automatically sorts elements

Question 3

What is the primary operational advantage of a Doubly Linked List over a Singly Linked List?

Accepted Answer

Bidirectional traversal (both forward and backward), and the ability to delete a given node in O(1) time without needing a pointer to the preceding node

Answer

It consumes half the memory of a singly linked list

Answer

It eliminates the need for pointers

Answer

It provides constant-time binary search

Question 4

What is Floyd's Cycle-Finding Algorithm ("Tortoise and Hare" algorithm) used for in a Linked List?

Accepted Answer

Detecting whether a linked list contains a loop / cycle using two pointers moving at different speeds (Slow pointer moving 1 step, Fast pointer moving 2 steps)

Answer

Sorting the linked list in alphabetical order

Answer

Counting the total number of characters in a string

Answer

Compressing the linked list

Question 5

What is the Best-Case time complexity of "Insertion Sort" when applied to an array that is ALREADY sorted in ascending order?

Accepted Answer

O(N) (linear time, making only N-1 comparisons and 0 swaps)

Answer

O(N^2)

Answer

O(N log N)

Answer

O(1)

Question 6

Which sorting algorithm operates by repeatedly finding the absolute minimum element from the unsorted subarray and swapping it with the first unsorted element, making exactly $\mathcal{O}(N)$ total swaps?

Accepted Answer

Selection Sort

Answer

Bubble Sort

Answer

Merge Sort

Answer

Quick Sort

Question 7

What does it mean for a sorting algorithm to be "Stable"?

Accepted Answer

It preserves the relative input order of records that have equal / identical key values

Answer

The algorithm never crashes the operating system

Answer

The algorithm uses constant auxiliary memory

Answer

The algorithm runs in linear time

Question 8

What is the correct structural order of the standard "CSS Box Model" layers starting from the innermost content outward?

Accepted Answer

Content -> Padding -> Border -> Margin

Answer

Content -> Margin -> Border -> Padding

Answer

Padding -> Content -> Margin -> Border

Answer

Border -> Padding -> Margin -> Content

Question 9

In CSS, what is the effect of setting `box-sizing: border-box;` on elements?

Accepted Answer

The element's declared `width` and `height` include both Content, Padding, and Border (padding and border do not add extra width to the element)

Answer

It draws a red border around all boxes

Answer

It converts all elements into flexbox containers

Answer

It deletes margins completely

Question 10

In CSS Flexible Box Layout (Flexbox), which property aligns flex items along the "Main Axis" (horizontally in a default row layout)?

Accepted Answer

justify-content

Answer

align-items

Answer

align-content

Answer

flex-direction

Question 11

Which JavaScript method is used to attach an event handler (such as a click listener) to an HTML DOM element?

Accepted Answer

element.addEventListener('click', function)

Answer

element.attachClick(function)

Answer

element.listen('click')

Answer

element.setEvent('click', function)

Question 12

Which modern JavaScript method selects the FIRST HTML element matching a specified CSS selector string (e.g. `.container .card`)?

Accepted Answer

document.querySelector()

Answer

document.querySelectorAll()

Answer

document.getElementBySelector()

Answer

document.find()

Question 13

What is the difference between the loose equality operator (`==`) and the strict equality operator (`===`) in JavaScript?

Accepted Answer

`==` performs automatic Type Coercion before comparing values (e.g. `5 == '5'` is TRUE); `===` checks both value AND data type without coercion (e.g. `5 === '5'` is FALSE)

Answer

`===` is for strings only

Answer

`==` is strictly for floating point numbers

Answer

`===` is unsupported in modern JavaScript

Question 14

How do ES6 "Arrow Functions" (`() => {}`) handle the `this` keyword compared to standard traditional function expressions in JavaScript?

Accepted Answer

Arrow functions do not have their own `this` binding; they inherit `this` lexically from the enclosing parent execution scope

Answer

Arrow functions bind `this` to the global `window` object always

Answer

Arrow functions cannot use variables

Answer

Arrow functions make `this` undefined

Question 15

Which two JavaScript methods convert a JavaScript object into a JSON string, and parse a JSON string back into a JavaScript object, respectively?

Accepted Answer

JSON.stringify() and JSON.parse()

Answer

JSON.encode() and JSON.decode()

Answer

JSON.serialize() and JSON.unserialize()

Answer

JSON.toText() and JSON.toObject()

Data Structures, Algorithms, Programming Concepts (C/C++/Python/Java), OOP & Web Development (Part 6)

In an array-based Circular Queue of size NNN, what mathematical pointer arithmetic formula is used to advance the `rear` index during an `enqueue()` operation?

In an array-based Circular Queue of size $N$ , what mathematical pointer arithmetic formula is used to advance the `rear` index during an `enqueue()` operation?