C++ Programming MCQ – Specialization

C++ interview questions and answers focuses on “Specialization “. One shall practice these interview questions to improve their C++ programming skills needed for various interviews (campus interviews, walk-in interviews, company interviews) entrance exams and other competitive exams. These questions can be attempted by anyone focusing on learning C++ programming language. They can be a beginner, fresher, engineering graduate or an experienced IT professional. Our C++ interview questions come with the detailed explanation of the answers which helps in better understanding of C++ concepts.
C++ interview questions on “Specialization ” along with answers, explanations and/or solutions:

Q 1. What is meant by template specialization?
A. Certain data types are invalid
B. It will make certain data types to be dynamic
C. It will have certain data types to be fixed
D. It will make all data types to be dynamic

Show Answer

Answer:-C. It will have certain data types to be fixed

Explanation

In the template specialization, it will make the template to be specific for some data types.

Q 2. Which is similar to template specialization?
A. function template overloading
B. function overloading
C. template
D. overloading

Show Answer

Answer:-A. function template overloading

Explanation

function template overloading is similar to template specialization.

Q 3. Which is called on allocating the memory for the array of objects?
A. constructor
B. destructor
C. method
D. class

Show Answer

Answer:-A. constructor

Explanation

When you allocate memory for an array of objects, the default constructor must be called to construct each object. If no default constructor exists, you’re stuck needing a list of pointers to objects.

Q 4. What will be the output of the following C++ code?

#include <iostream>
using namespace std;
template <class T>
inline T square(T x)
{
T result;
result = x * x;
return result;
};
template <>
string square<string>(string ss)
{
return (ss+ss);
};
int main()
{
int i = 2, ii;
string ww(“A”);
ii = square<int>(i);
cout << i << “: ” << ii;
cout << square<string>(ww) << “:” << endl;
}
A. 2: 4AA:
B. 2:4
C. AA
D. 2:4A

Show Answer

Answer:-A. 2: 4AA:

Explanation

Template specialization is used when a different and specific implementation is to be used for a specific data type. In this program, We are using integer and character. Output: $ g++ spec.cpp $ a.out 2: 4AA:

Q 5. What will be the output of the following C++ code?

#include <iostream>
using namespace std;
template <typename T = float, int count = 3>
T multIt(T x)
{
for(int ii = 0; ii < count; ii++)
{
x = x * x;
}
return x;
};
int main()
{
float xx = 2.1;
cout << xx << “: ” << multIt<>(xx) << endl;
}
A. 2.1
B. 378.228
C. 376
D. 2.1: 378.228

Show Answer

Answer:-D. 2.1: 378.228

Explanation

In this program, We specify the type in the template function. We need to compile this program by adding -std=c++0x. Output: $ g++ -std=c++0x spec1.cpp $ a.out 2.1: 378.228

Q 6. What will be the output of the following C++ code?

#include <iostream>
using namespace std;
template <class T>
class XYZ
{
public:
void putPri();
static T ipub;
private:
static T ipri;
};
template <class T>
void XYZ<T>::putPri()
{
cout << ipri++ << endl;
}
template <class T> T XYZ<T>::ipub = 1;
template <class T> T XYZ<T>::ipri = 1.2;
int main()
{
XYZ<int> a;
XYZ<float> b;
a.putPri();
cout << a.ipub << endl;
b.putPri();
}
A. 1
B. 1.2
C. 1
1.2
D. 1
1
1.2

Show Answer

Answer:-D. 1 1 1.2

Explanation

In this program, We are passing the value of specified type and printing it by specialization. Output: $ g++ spec2.cpp $ a.out 1 1 1.2

Q 7. What will be the output of the following C++ code?

#include <iostream>
#include <string>
#include <cstring>
using namespace std;
template <class type>
type MyMax(const type Var1, const type Var2)
{
cout << “no specialization”;
return Var1 < Var2 ? Var2 : Var1;
}
template <>
const char *MyMax(const char *Var1, const char *Var2)
{
return (strcmp(Var1, Var2)<0) ? Var2 : Var1;
}
int main()
{
string Str1 = “class”, Str2 = “template”;
const char *Var3 = “class”;
const char *Var4 = “template”;
const char *q = MyMax(Var3, Var4);
cout << q << endl;
return 0;
}
A. class
B. template
C. no specialization
D. templateclass

Show Answer

Answer:-B. template

Explanation

In this program, We are computing the result in the specialized block of the program. Output: $ g++ spec3.cpp $ a.out template

Q 8. What will be the output of the following C++ code?

#include <iostream>
using namespace std;
template<class T = float, int i = 5> class A
{
public:
A();
int value;
};
template<> class A<>
{
public: A();
};
template<> class A<double, 10>
{
public: A();
};
template<class T, int i> A<T, i>::A() : value(i)
{
cout << value;
}
A<>::A()
{
cout << “default”;
}
A<double, 10>::A()
{
cout << “10” << endl;
}
int main()
{
A<int, 6> x;
A<> y;
A<double, 10> z;
}
A. 6
B. 10
C. 6default10
D. 6default

Show Answer

Answer:-C. 6default10

Explanation

In this program, We are defining three templates and specializing it and passing the values to it and printing it. Output: $ g++ spec5.cpp $ a.out 6default10

Q 9. How many types of specialization are there in c++?
A. 1
B. 2
C. 3
D. 4

Show Answer

Answer:-D. 4

Explanation

There are two types of specialization. They are full specialization and partial specialization.

Q 10. What is another name of full specialization?
A. explicit specialization
B. implicit specialization
C. function overloading template
D. overloading template

Show Answer

Answer:-A. explicit specialization

Explanation

explicit specialization is another name of full specialization.