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The correct OPTION is (a) Iterator

The BEST explanation: The CONTAINER manages the STORAGE SPACE for its elements and provides member functions to access them, either directly or through iterators which reference objects with similar properties to pointers.

Correct answer is (C) both new & delete

The best I can EXPLAIN: new and delete operators are USED to allocate and deallocate the MEMORY for the program.

The correct option is (a) Information about an object’s DATA type at RUNTIME

Easiest explanation - With the help of RTTI, We can GET the information about the data type at the runtime.

Correct ANSWER is (B) Deriving NEW classes from EXISTING classes

The best explanation: INHERITANCE is the concept of OOPs in which new classes are derived from existing classes in order to reuse the properties of classes defined earlier.

Correct option is (a) Standard LOGGING stream

Easy explanation - clog is an object of class ostream that REPRESENTS the standard logging stream. It is ASSOCIATED with the cstdio stream stderr, like CERR.

Right option is (d) priority queue

For explanation: C++ provides priority queue container that stores elements BASED on their priority. For EXAMPLE, if the ABSOLUTE value is the priority then -6 will be kept before 4 in the priority queue.

Right ANSWER is (d) 4

The EXPLANATION is: There can be FOUR TYPES of an ASSOCIATION relationship between classes namely one-to-one, one-to-many, many-to-one and many-to-many.

Correct CHOICE is (d) All of the mentioned

Best EXPLANATION: A pair can be assigned, copied or can be COMPARED. Hence all the above operations can e performed on PAIRS.

The correct OPTION is (b)

Easy explanation - PAIR CONTAINER is DEFINED under the header file THEREFORE one should includeheader before using pair container.

Correct CHOICE is (b) v.capacity()

The best explanation: capacity() FUNCTION is used to get the total number of elements that can be stored at PRESENT in the vector.

The correct option is (c) INSERTION in vectors always takes CONSTANT time

Explanation: Insertion in vectors are not always constant. When we are inserting an element at the end of the vector then if a vector is FULL then it needs to size itself which takes time to resize and time to insert element else just time for inserting that element at the end. Hence the insertion time is not constant always. Vectors have a dynamic size. They are placed in contiguous MEMORY for easy access.

The correct CHOICE is (c) both at() and GET()

Explanation: Both at() and get() function are used to ACCESS the elements stored at i’TH position of the array.

The correct option is (a) ITERATOR type

Explanation: Every container MUST define an iterator type. ITERATORS allow algorithms to iterate over the container’s CONTENTS.

Correct answer is (a) STD:map

Explanation: LOOKUP table means storing values in a table with unique keys for each value so that can be CHECKED in future easily. So for such lookup tables maps are USED in C++.

The correct option is (C) Freestore

Easy EXPLANATION - Free STORE is a pool of memory available for you to allocate and deallocate STORAGE for objects during the execution of your PROGRAM.

Correct ANSWER is (C) both dynamic_cast<> & typeid

Explanation: The dynamic_cast<> operation and typeid operator in C++ are part of RTTI.

Right CHOICE is (C) 3

To EXPLAIN: There are 3 specifiers USED to DERIVE a class. They are private, protected and public.

The correct option is (b) Classes express FUNCTIONALITY which represents responsibilities

The best I can explain: A class that EXPRESSES functionality rather than its PRIMARY design role is CALLED a MIXIN.

The correct OPTION is (a) Is-A relationship

Best explanation: Inheritance models Is-A TYPE of relationship between classes. This is because in this case DERIVED class inherits all property of the BASE class and Is-A type of B class.

The correct choice is (c) Returns TRUE if any bit is SET 1

The best explanation: header PROVIDES the any() FUNCTION which returns true if any of the bit is set to 1 in the bitset variable.

The CORRECT choice is (d) RETURNS the size of a GIVEN dimension

Best explanation: The EXTENT() function takes two parameters one DENOTING the array other showing the dimension for which the size we want to know.

The CORRECT answer is (d) <RANDOM>

Easiest explanation - header FILE is REQUIRED for using GENERATORS and distributions which helps in generating random numbers in a program.

Correct answer is (a) VECTOR POINTER

To explain: VPTR is abbreviated for a virtual pointer which is USED to POINT virtual tables of a class.

Correct choice is (b) bad_any_cast

Best explanation: bad_any_cast exception is thrown when TYPECASTING is not done properly by the USER i.e. if any is storing INT value and we are TRYING to cast it into a string then the program will throw bad_any_cast exception.

Correct choice is (c) begin() returns an ITERATOR to first element whereas cbegin() returns constant iterator to first element

The best I can explain: Both begin() and cbegin() are used to ACCESS the first element of the VECTOR. The function begin() returns an iterator to first element whereas cbegin() returns a constant iterator to first element.

The CORRECT ANSWER is (a) Sequence Container ARRAYS know (somehow stores within) its size whereas C-like arrays do not

To explain: Sequence CONTAINERS Arrays stores its size within itself so need to pass extra size parameter when passing this ARRAY as an argument.

The correct choice is (c) 3

Best explanation: There are three main ITERATORS needed for designing a container. They are CONST iterator, REVERSE iterator and Iterator traits.

Right CHOICE is (b) Generic

The explanation is: The STL is a generic LIBRARY, MEANING that its COMPONENTS are heavily parameterized.

Right option is (a) SEPARATION of interface from implementation

The BEST I can EXPLAIN: Separation of interface from implementation INTRODUCE the interface of classes in a run-time POLYMORPHIC hierarchy.

The correct answer is (a) binary search tree

Explanation: Sets are implemented USING the search tree so that we can CHECK the presence of any element to be INSERTED in O(logn) time in order to REMOVE conflicts between elements.

Correct option is (d) All of the mentioned

Explanation: The Class relationship is a CONCEPT that helps us in DIFFERENTIATING how ONE class is RELATED to other classes, the power of one over other and which part one class can be accessed by other class.

Correct choice is (b) Returns true if all bits is set 0

Easiest EXPLANATION - HEADER PROVIDES the any() FUNCTION which returns true if none of the bit is set to 1 in the bitset variable.

The CORRECT ANSWER is (a) <COMPLEX>

Easiest EXPLANATION - header file is required to use the functionalitites of complex NUMBERS.

Right answer is (b) make_heap()

The EXPLANATION: C++ STL-heap CONTAINER provides make_heap() FUNCTION to convert a GIVEN range of number into heap.

Right choice is (b) LIFO

Easiest EXPLANATION - A stack is a container where elements OPERATE in a LIFO CONTEXT, where elements are inserted (PUSHED) and removed (POPPED) from the end of the container.

Right choice is (a) Used to HOLD the type INFORMATION RETURNED by the typeid operator

The BEST I can explain: type_info is used to hold the type information returned by the typeid operator.

Correct option is (d) hash table

Easiest explanation - As unordered MAP has no order of KEYS therefore hash table is USED to store key-value PAIRS in a hash table.

The correct OPTION is (b) multimap

To explain I would SAY: C++ provide multimap CONTAINER that is USED to MAKE map that can contain same keys i.e. {a: 5} and {a:10} both can exist.

Correct answer is (B) complex variable_name;

Best explanation: The correct SYNTAX of DECLARING a complex number OBJECT is complex variable_name.

Correct ANSWER is (d) make_heap(v.begin(), v.end());

The explanation: To construct HEAP USNG the vector elements one need to use the FOLLOWING syntax make_heap(v.begin(), v.end()); which is taking the ITERATOR to first and last element of the vector using which elements of vector can be accessed and heap can be constructed.

The CORRECT choice is (c) Returns the first element of the heap

Easiest EXPLANATION - C++ STL-heap CONTAINER provides the front() function that returns the first element of the heap i.e. the MAXIMUM number of the sequence.

Right answer is (d) vectors do not have a function to access the last element

The EXPLANATION: There are no function to access the last element of the VECTOR. The end() and CEND() returns the ITERATOR to an element which is kept at the last of the vector to keep the knowledge about the end of a vector. In order to access the last element, you can first find the size and then can use V[size-1] or v.at(size – 1) to access the last element.

Right choice is (d) NONE of the mentioned

Explanation: All the data members and member FUNCTIONS of a class are PRIVATE by DEFAULT.