Explore topic-wise InterviewSolutions in .

The correct choice is (c) 3

Best EXPLANATION: The OBJECTS can be passed in three WAYS. Pass by VALUE, pass by reference and pass by address. These are the general ways to pass the objects to a function.

Right answer is (a) A NEW copy of object is CREATED IMPLICITLY

The explanation is: When an object is PASSED by value, a new object is created implicitly. This new object uses the implicit values assignment, same as that of the object being passed.

The correct choice is (a) Are REFLECTED to the main OBJECT of caller function too

The best I can EXPLAIN: When an object is PASSED by REFERENCE, its address is passed implicitly. This will make changes to the main function whenever any modification is done.

Correct option is (b) Yes, MUST be called

To explain: EVEN THOUGH the constructor is not called when the object is passed to a FUNCTION, the copy of the object is still created, where the values of the members are same. When the object have to be destroyed, the destructor is called to free the MEMORY and resources that the object might have reserved.

The correct OPTION is (d) Overloading assignment operator and defining copy constructor

Explanation: The problem can be SOLVED by overloading the assignment operator to get the values that might be getting returned while the destructor free the dynamic memory. Defining copy constructor can help us to do this in EVEN simpler way.

The CORRECT option is (a) Only 1

Easiest explanation - LIKE any other VALUE, only one object can be returned at ones. The only POSSIBLE way to return more than one object is to return address of an object array. But that again comes under returning object pointer.

The correct option is (c) No, the changes are MADE automatically

The explanation: Having the address being PASSED to the function, the changes are automatically made to the main function. In all the cases if the address is being used, the same memory LOCATION will be UPDATED with NEW values.

Correct option is (d) As many as required

The EXPLANATION is: There is no limit to how many objects can be PASSED. This works in same way as that any other VARIABLE GETS passed. Array and object can be passed at same time ALSO.

The correct option is (c) No, values are copied

Best explanation: A copy of all the values is CREATED. If the constructor is called, there will be a compile time ERROR or memory shortage. This happens because each time a constructor is called, it TRY to call itself again and that goes infinite TIMES.

Correct CHOICE is (a) No, DUPLICATE declaration is not allowed

Easy explanation - There can’t be more than one VARIABLE or object with the same NAME in same scope. The scope is same, since the object is passed, it becomes local to FUNCTION and hence function can’t have one more object of same name.

Correct option is (B) False

To explain: The copy constructor is used to copy the VALUES from ONE object to other. PASS by values is not same as copy constructor method. Actually the pass by value method uses a copy constructor to copy the values in a LOCAL object.

The correct choice is (a) It can never be reassigned to REFER to a different object

Easiest explanation - Since the VARIABLE is declared FINAL. It will have a CONSTANT value throughout the program. It can refer to only ONE object at a time. And if it was made to refer to none of the object, it would have got no use.

Correct option is (a) MEMBERS of class where this is USED

Explanation: We use this pointer to differentiate the members of the class where this is used to the other INHERITED or passed variables. The LOCAL variables are denoted with this. Or SPECIFICALLY the members of class only.

The correct option is (d) depends on where the method is being called

Explanation: This depends on where the method is being called. If the method is called inside the enclosing class itself. Then we can’t USE OBJECT of enclosing class. If the method is being called WITHIN the inner class itself, then its object will ALSO be of no use.

Right CHOICE is (a) One at a time

For EXPLANATION: There should not be any CONFUSION in how many references can be made from a single variable. A single variable can only point to one object at a time. EVEN if it’s an ARRAY, the name of the array is used and is considered one object name only (representing first array element).

Right option is (a) True

To explain: In Java, it is inbuilt feature that HANDLES all the memory dynamically. It is not necessary to free or DESTROY all the REFERENCES MADE from a FUNCTION which is going out of scope. You can call destroy or free methods explicitly but there is no mandatory rule.

Correct choice is (c) Object REFERENCING points to same address, if assigned by variables

Explanation: The object referencing will POINT to the same address if variables are assigned. All the variables might have a DIFFERENT name but they will point to the same memory location. This is most basic concept of references.

Correct answer is (a) Its compile time error

Explanation: It is a compile time error as the COMPILER doesn’t allow the same name OBJECTS to be DECLARED more than once. Compiler produces multiple declaration errors. Every OBJECT must have a different name.

Correct answer is (c) As only one class TYPE at a time

To explain: The object can be of only one type. The type of an object can’t be changed. Object type is mandatory to be of one class type to ENSURE the type and NUMBER of data members it have.

Correct OPTION is (b) cin

Explanation: OBJECT cin can be USED to take input from the standard input. It is used in C++. In java we can use System.in for the standard input stream. The SYNTAX CHANGES from language to language.

The correct answer is (a) A REAL world entity

Easiest EXPLANATION - The OBJECTS are actually meant to represent an entity. The classes are real world object’s blueprint. The classes then are USED to create an entity REPRESENTATION.

The correct option is (b) Can’t be CHANGED in runtime

Best EXPLANATION: The object TYPES are always FIXED. Once the object is created of a SPECIFIC type then it can’t be changed. Neither at runtime nor at compile time.

The correct ANSWER is (a) Can be used directly with << and >> symbols respectively

The EXPLANATION is: The cin and COUT OBJECTS can be used directly with the >> and << operators respectively. The objects are of iostream class. Class iostream is an INBUILT class.

The CORRECT option is (B) The only object of a class THROUGHOUT the program

For explanation: If a class has only ONE object created and that is the only object of the class. Then the object is known as the SINGLETON object. But only if that object is the only object of the class and no other object is created for that class.

Correct choice is (d) To CREATE new objects

The best explanation: The factory object is an object that can be used to create other objects. If it is seen formally, it behaves like a METHOD that will RETURN object on its use. The object RETURNED is ASSUMED to be a new object.

The correct CHOICE is (a) To set up as a fixed state

Easiest explanation - An immutable object can be created for an object which has to be fixed with values. The object DATA will not be changed throughout the program. This can be useful to ELIMINATE the unintentional changes in the data of object.

The CORRECT CHOICE is (a) An object with a single function

The best I can explain: A function object is an object with single function. In C++ a function object can be like OPERATOR() function. This acts more like a function RATHER than an object.

The CORRECT answer is (d) NAMES

The explanation is: The names are not property of an object. The IDENTITY can be in any form LIKE address or name of object but name can’t be TERMED as only identity of an object. The objects contain attributes that define what type of data an object can store.

Correct answer is (d) No, never

The explanation is: The character arrays are not the same as STRING. The string once CREATED then remains the same. The character array values MAY change.

The correct choice is (B) False

Explanation: The TWO dimensional arrays can also be initialized using curly brackets. For each set, values in curly bracket. And then another bracket is ADDED at first and end. This ENSURES that all the code BELONGS to the user.

Right choice is (a) 0

For EXPLANATION: The index must START from 0. The index ends at SIZE – 1 index. This is because the index is ALWAYS TILL n-1 where n is the total number of beads.

Correct ANSWER is (a) YES, always

Explanation: A two DIMENSIONAL array can always be created. There is no rule that only PRIMITIVE type objects can have more than one dimension. The object array can also be made 2 dimensional.

Correct answer is (a) Array_Name[4].data_variable_name;

The explanation is: The array NAME with the index of fifth element is CALLED, i.e. index 4. Then the dot operator is USED to access the data member of that OBJECT. This Allows us to access the data members of all the objects in an object array.

The correct option is (a) HEAP memory

To explain I would SAY: If the object arrays are DECLARED dynamically, then the memory will be reserved on heap. The memory for objects will be on stack only if some constructor or some call and RETURN tasks are happening. The program doesn’t run on HDD and ROM is not used for the execution of PROGRAMS.

Right answer is (b) Can be created WITHOUT calling default CONSTRUCTOR

The explanation is: The objects need some constructor to get the memory spaced reserved for those. If the default constructor is not used then we can use some ARGUMENTS constructor which will RESERVE the memory for the objects. The objects can be passed with constructor arguments during declaration.

The correct OPTION is (a) Indices

To explain I would say: Different objects in an array can be DENOTED with the indices of array. The first object is denoted by 0. And the further indices DENOTE the NEXT objects in sequence of array.

Correct answer is (C) It is not mandatory to call same constructor for all the objects

The best I can explain: It is not mandatory to call the same constructor for all the objects in an array if INITIALIZED with the declaration. The objects can be passed with DIFFERENT set of arguments in the same SYNTAX, separated by commas.

The correct option is (a) When object data is not REQUIRED just after the declaration

The explanation: Sometimes the object data is not mandatory to be used just after the declaration or may be the program REQUIRES the data to be updated ACCORDING to what USER inputs. Hence only declaration us also useful.

The correct answer is (d) The class MUST have a default or zero argument constructor

Explanation: The class must have a default/zero argument constructor. Since the declaration is done by only specifying the size of ARRAY, the class must have default a construct to be called by default to reserve MEMORY for each object. Also, we can’t specify the ARGUMENTS in this type of declaration HENCE the class should provide a default initialization.

The CORRECT answer is (a) Class

To explain I would say: The class itself is the type of elements of array of OBJECTS. All the objects possess the same properties. Like any other PRIMITIVE DATA type, the objects are of their respective class type.

Right choice is (C) All the OBJECTS should be of same CLASS

To explain: The objects of an array must be of same class. This is mandatory because array is set of same type of elements. The objects of same class are considered to be of same type.

Correct CHOICE is (a) An ARRAY of instances of class represented by single name

The best I can explain: The array of objects an array of instances of a class. The array is represented by a single name. The array name is itself a pointer. Array name REPRESENTS the FIRST OBJECT.

Correct ANSWER is (b) delete

The best explanation: The delete operator in C++ can be used to FREE the memory and resources held by an object. The function can be called EXPLICITLY whenever REQUIRED. In C++ memory management must be done by the programmer. There is no automatic memory management in C++.