Data Structures and Algorithms in C++ Exam Questions and Answers Latest Update 2025-2026
Maps (Associative Arrays) - Answers Key-value pairs where each key is unique.
map.count(key) - Answers Returns 1 if the key exists, 0 otherwise.
map[key] - Answers Returns the value (inserts with default value if key doesn't exist).
Vectors - Answers Dynamic arrays allowing flexible resizing.
Access elements using vector[index] - Answers Method to retrieve elements from a vector.
Queues (FIFO) - Answers First In, First Out.
Task scheduling - Answers Example of a queue.
enqueue - Answers Operation to add an element to the queue.
dequeue - Answers Operation to remove an element from the queue.
Stacks (LIFO) - Answers Last In, First Out.
Postfix (RPN) notation - Answers Example: 3 4 + means 3 + 4 = 7.
Arrays - Answers Fixed-size, contiguous memory.
Access with array[index] - Answers Method to retrieve elements from an array.
Big O Notation: Selection Sort - Answers O(n²) — Inefficient for large datasets. Compares each element
with others.
Big O Notation: Binary Search - Answers O(log n) — Efficient search in a sorted array by dividing the
search space.
Binary Search in Maps - Answers Logarithmic time O(log n) due to sorted key structure in std::map.
Recursion Techniques - Answers Break the problem into smaller parts, use base cases to stop recursion.
C++ Classes: Constructors - Answers Special functions to initialize objects.
Example: Money(int dollars, int cents) - Answers Constructor example for a Money class.
C++ Classes: Operator Overloading - Answers Customize behavior for operators between objects.
Example: Overload + - Answers To add two Money objects.
Range-Based For Loops - Answers Efficient iteration over collections.
Example: for (char ch : str) - Answers Example of a range-based for loop.
Maps (Associative Arrays) - Answers Key-value pairs where each key is unique.
map.count(key) - Answers Returns 1 if the key exists, 0 otherwise.
map[key] - Answers Returns the value (inserts with default value if key doesn't exist).
Vectors - Answers Dynamic arrays allowing flexible resizing.
Access elements using vector[index] - Answers Method to retrieve elements from a vector.
Queues (FIFO) - Answers First In, First Out.
Task scheduling - Answers Example of a queue.
enqueue - Answers Operation to add an element to the queue.
dequeue - Answers Operation to remove an element from the queue.
Stacks (LIFO) - Answers Last In, First Out.
Postfix (RPN) notation - Answers Example: 3 4 + means 3 + 4 = 7.
Arrays - Answers Fixed-size, contiguous memory.
Access with array[index] - Answers Method to retrieve elements from an array.
Big O Notation: Selection Sort - Answers O(n²) — Inefficient for large datasets. Compares each element
with others.
Big O Notation: Binary Search - Answers O(log n) — Efficient search in a sorted array by dividing the
search space.
Binary Search in Maps - Answers Logarithmic time O(log n) due to sorted key structure in std::map.
Recursion Techniques - Answers Break the problem into smaller parts, use base cases to stop recursion.
C++ Classes: Constructors - Answers Special functions to initialize objects.
Example: Money(int dollars, int cents) - Answers Constructor example for a Money class.
C++ Classes: Operator Overloading - Answers Customize behavior for operators between objects.
Example: Overload + - Answers To add two Money objects.
Range-Based For Loops - Answers Efficient iteration over collections.
Example: for (char ch : str) - Answers Example of a range-based for loop.
