Deck 4: C++ Programming and Concepts: Inheritance, Data Types, Objects, and Output Prediction

Question 1

C++ was originally developed by ….......

A)donald knuth
B)bjarne sroustrups
C)dennis ritchie
D)none of these

Answer 1

bjarne sroustrups

Question 2

Which of the following approach is adopted in C++?

A)top down
B)bottom up
C)horizontal
D)vertical

Answer 2

bottom up

Question 3

Which feature of C++ contain the concept of super class and subclass?

A)class and object
B)encapsulation
C)abstraction
D)inheritance

Answer 3

inheritance

Question 4

The main intention of using inheritance is ….........

A)to help in converting one data type to other
B)to hide the details of base class
C)to extend the capabilities of base class
D)to help in modular programming

Question 5

If particular software can be used in some other application than the one for which it is created then it reveals ….........

A)data binding
B)data reusability
C)data encapsulation
D)none of these

Question 6

Which of the following data type does not return anything?

A)int
B)short
C)long
D)void

Question 7

How many objects can be created from an abstract class?

A)zero
B)one
C)two
D)as many as we want

Question 8

Which of the following statements is correct for a static member function?
1) It can access only other static members of its class.
2) It can be called using the class name, instead of objects

A)only 1 is correct
B)only 2 is correct
C)both 1 and 2 are correct
D)both 1 and 2 are incorrect

Question 9

What happens when a class with parameterized constructors and having no default constructor is used in a program and we create an object that needs a zero-argument constructor?

A)compile-time error
B)preprocessing error
C)runtime error
D)runtime exception

Question 10

Which of the following interface determines how your program will be used by other program?

A)public
B)private
C)protected
D)none of these

Question 11

What is the difference between struct and class in C++?

A)all members of a structure are public and structures don't have constructors and destructors
B)members of a class are private by default and members of struct are public by default. when deriving a struct from a class/struct, default access-specifier for a base class/struct is public and when deriving a class, default access specifier is private.
C)all members of a structure are public and structures don't have virtual functions
D)all above

Question 12

Predict the output of following C++ program#include<iostream> using namespace std;class Empty {}; int main(){cout <<sizeof(Empty); return 0;}

A)a non zero value
B)0
C)compile time error
D)runtime error

Question 13

class Test { int x;};int main(){Test t; cout <<t.x; return 0;}

A)0
B)garbage value
C)compile time error

Question 14

Which of the following is true?

A)all objects of a class share all data members of class
B)objects of a class do not share non-static members. every object has its own copy
C)objects of a class do not share codes of non-static methods, they have their own copy
D)none

Question 15

Which of the following is true about the following program#include <iostream> class Test{public:int i;void get();};void Test::get(){std::cout <<"Enter the value of i: "; std::cin >>i;}Test t; // Global object int main(){Test t; // local object t.get();std::cout <<"value of i in local t: "<<t.i<<'\n';::t.get();std::cout <<"value of i in global t: "<<::t.i<<'\n'; return 0;}

A)compiler error: cannot have two objects with same class name
B)compiler error in line "::t.get();"
C)compiles and runs fine

Question 16

Which of the following is true about new when compared with malloc.
1) new is an operator, malloc is a function
2) new calls constructor, malloc doesn't
3) new returns appropriate pointer, malloc returns void * and pointer needs to typecast to appropriate type.

A)1 and 3
B)2 and 3
C)1 and 2
D)all 1,2,3

Question 17

Predict the output?#include <iostream> using namespace std;class Test{int x;Test() { x = 5;}};int main(){Test *t = new Test; cout <<t->x;}

A)compile time error
B)garbage
C)0
D)5

Question 18

What happens when delete is used for a NULL pointer? int *ptr = NULL; delete ptr;

A)compile time error
B)run time error
C)no effect

Question 19

Is it fine to call delete twice for a pointer?#include<iostream> using namespace std;int main(){int *ptr = new int; delete ptr;delete ptr; return 0;}

Question 20

Which of the followings is/are automatically added to every class, if we do not write our own.

A)copy constructor
B)assignment operator
C)a constructor without any parameter
D)all of the above

Question 21

Output of following program?#include<iostream> using namespace std; class Point {Point() { cout <<"Constructor called"; }};int main(){Point t1; return 0;}

A)compile time error
B)run time error
C)constructor called

Question 22

#include<iostream> using namespace std; class Point {public:Point() { cout <<"Constructor called"; }};int main(){Point t1, *t2; return 0;}

A)compiler error
B)constructor called constructor called
C)constructor called

Question 23

#include<iostream> using namespace std;class X{public:int x;};int main(){X a = {10};X b = a;cout <<a.x <<" " <<b.x; return 0;}

A)compiler error
B)10 followed by garbage value
C)10 10
D)10 0