C++ Multiple Choice Questions for Practitioners

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Question: 76

What is true about his statement in C++?
std::vector<int> vecInts(5);

(A) Initialize a Vector with 5 int & all default value is 0
(B) Initialize a Vector with 5 int
(C) Initialize a Vector with 5 int & all default values will be garbage
(D) Initialize a Vector with 5 int & All default value with be -1

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Level: Practitioner

Category of MCQ: stl in C++

Question: 77

Is it possible to initialize any Vector with an Array in C++?

(A) Yes
(B) No

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Level: Practitioner

Category of MCQ: stl in C++

Question: 78

Will below program run without any compilation errors?
Assume that all header files are included.

int main()
{

std::list<std::string> listOfStr;
listOfStr.push_back("1");
listOfStr.push_back("2");
listOfStr.push_back("3");
listOfStr.push_back("4");
 
// Initialize a vector with std::list
std::vector<std::string> vecOfStr(listOfStr.begin(),listOfStr.end());
 
for(std::string str : vecOfStr)
    std::cout<<str<<std::endl;

return 0;
}

(A) Yes
(B) No

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Level: Practitioner

Category of MCQ: stl in C++

Question: 79

What should be the output of below program? Assume that all header files are included.

int main()
{
std::list<std::string> listOfStr;
listOfStr.push_back("1");
listOfStr.push_back("2");
listOfStr.push_back("3");
listOfStr.push_back("4");
 
// Initialize a vector with std::list
std::vector<std::string> vecOfStr(listOfStr.begin(), listOfStr.end());
 
for(std::string str : vecOfStr)
    std::cout<<str;

return 0;
}

(A) 1 2 3 4
(B) 1234
(C) 12340
(D) 01234

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Level: Practitioner

Category of MCQ: stl in C++

Question: 80

What does this function do?

void func() {
	std::vector<std::string> vecOfString(5, "Hi");
 
	for (std::string str : vecOfStr)
		std::cout << str << std::endl;
 
}

(A) Initialize vect to 5 string with value "Hi"
(B) Initialize vect's first element to a string with value "Hi" & prints them
(C) Initialize vect to 1 string with value "Hi" & prints only one
(D) Initialize vect to 5 string with value "Hi" & prints them

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Level: Practitioner

Category of MCQ: stl in C++

Question: 81

Which of the following statements opens a file and links it to a file stream object?

(A) file.open(“c:filename.txt”);
(B) open(afile) = link(anObject);
(C) linkstream(“filenemae.txt”)
(D) link(open(filename.txt);

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Level: Practitioner

Category of MCQ: filehandling in C++

Question: 82

The end-of-file marker is automatically written when a file is closed

(A) TRUE
(B) FALSE

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Level: Practitioner

Category of MCQ: filehandling in C++

Question: 83

When a file is opened by the program, the file stream object’s “read position” is

(A) At the end of the file
(B) At the beginning of the file
(C) Nonexistent until the program declares it
(D) There is no read position

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Level: Practitioner

Category of MCQ: filehandling in C++

Question: 84

#include <iostream>
using namespace std;
class TestingClass
{
public:
TestingClass(int x)
{
 cout << x << endl; 
}

TestingClass()
{
 cout <<"Hello!"<< endl; 
}

};
int main()
{
 TestingClass test(77);
 return 0;
}

(A) The programs runs with no output
(B) 77
(C) Hello!
(D) Hello!

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Level: Practitioner

Category of MCQ: classesAndobjects in C++

Question: 85

A class can have only one constructor

(A) True
(B) False

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Level: Practitioner

Category of MCQ: classesAndobjects in C++

Question: 86

Which directive is used to create an “include guard”,
which allows a program to be conditionally compiled.
This prevents a header file from being included more than once

(A) #include
(B) #guard
(C) #ifndef
(D) endif

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Level: Practitioner

Category of MCQ: other in C++

Question: 87

An overloaded operator works with user defined data types

(A) True
(B) False

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Level: Practitioner

Category of MCQ: operators in C++

Question: 88

When you redefine the way a standard operator works when it is used with class objects, you have done?

(A) re-assigned
(B) reformatted
(C) constructed
(D) overloaded

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Level: Practitioner

Category of MCQ: operators in C++

Question: 89

If you overload the prefix ++ operator, the postfix ++ operator is automatically overloaded

(A) True
(B) False

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Level: Practitioner

Category of MCQ: operators in C++

Question: 90

It is possible to declare an entire class as a friend of another class

(A) True
(B) False

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Level: Practitioner

Category of MCQ: classesAndobjects in C++

Question: 91

If a member variable is declared as one of the below, all objects of that class have access to that variable.

(A) static
(B) auto
(C) exterb
(D) register

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Level: Practitioner

Category of MCQ: classesAndobjects in C++

Question: 92

What type of function is not a member of a class, but has access to the private members of the class.

(A) Static function
(B) constructor
(C) destructor
(D) friend

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Level: Practitioner

Category of MCQ: function in C++

Question: 93

When is the external name of the file used in the program

(A) Any time you read or write to the file
(B) Never
(C) Only when reading from the file
(D) When opening the file stream

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Level: Practitioner

Category of MCQ: filehandling in C++

Question: 94

In C++, if you overload the < operator, you must also overload TRUE FALSE the > operator

(A) True
(B) False

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Level: Practitioner

Category of MCQ: operators in C++

Question: 95

By default, when an object is assigned to another,
each member of one object is copied to its counterpart in the other object.

(A) True
(B) False

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Level: Practitioner

Category of MCQ: classesAndobjects in C++

Question: 96

this pointer is a special built-in pointer that is automatically
passed as a hidden argument to all non-static member functions

(A) True
(B) False

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Level: Practitioner

Category of MCQ: pointers in C++

Question: 97

Which of following allows us to create new classes based on existing classes

(A) Polymorphism
(B) Inheritance
(C) Function overloading
(D) None of these

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Level: Practitioner

Category of MCQ: inheritance in C++

Question: 98

A virtual function is declared by placing the
key word ___ in front of the return type in 
the base class’s function declaration

(A) virtual
(B) private
(C) public
(D) protected

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Level: Practitioner

Category of MCQ: virtual_func in C++

Question: 99

A virtual function is a function that expects to be overridden in a derived class

(A) True
(B) False

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Level: Practitioner

Category of MCQ: virtual_func in C++

Question: 100

The statement below declares a pure virtual function, and must be overridden in derived classes:
virtual void function() = 0;

(A) True
(B) False

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Level: Practitioner

Category of MCQ: virtual_func in C++

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