C++ Language Interview Questions - Operators

This section on C++ language interview questions and answers focuses on “Operators”. One shall practice these interview questions to improve their C++ programming skills needed for various interviews (campus interviews, walkin interviews, company interviews), placements, 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++ language interview questions come with detailed explanation of the answers which helps in better understanding of C++ concepts.

Here is a listing of C++ language interview questions on “Operators” along with answers, explanations and/or solutions:

1. Which operator is having right to left associativity in the following?
a) Array subscripting
b) Function call
c) Addition and subtraction
d) Type cast
View Answer

Answer: d
Explanation: None.

2. Which operator is having the highest precedence?
a) postfix
b) unary
c) shift
d) equality
View Answer

Answer: a
Explanation: The operator which is having highest precedence is postfix and lowest is equality.

3. What is this operator called ?: ?
a) conditional
b) relational
c) casting operator
d) none of the mentioned
View Answer

Answer: a
Explanation: In this operator, if the condition is true means, it will return the first operator, otherwise second operator.

4. What is the output of this program?

```
    #include <iostream>
```
```
    using namespace std;
```
```
    int main()
```
```
    {
```
```
        int a;
```
```
        a = 5 + 3 * 5;
```
```
        cout << a;
```
```
        return 0;
```
```
    }
```

a) 35
b) 20
c) 25
d) 30
View Answer

Answer: b
Explanation: Because the * operator is having highest precedence, So it is executed first and then the + operator will be executed.
Output:
$ g++ op1.cpp
$ a.out
20

5. What is the use of dynamic_cast operator?
a) it converts virtual base class to derived class
b) it converts virtual base object to derived objeccts
c) it will convert the operator based on precedence
d) none of the mentioned
View Answer

Answer: a
Explanation: Because the dynamic_cast operator is used to convert from base class to derived class.

6. What is the output of this program?

```
    #include <iostream>
```
```
    using namespace std;
```
```
    int main()
```
```
    {
```
```
        int a = 5, b = 6, c, d;
```
```
        c = a, b;
```
```
        d = (a, b);
```
```
        cout << c << ' ' << d;
```
```
        return 0;
```
```
    }
```

a) 5 6
b) 6 5
c) 6 7
d) none of the mentioned
View Answer

Answer: a
Explanation: It is a separtor here.In c,the value a is stored in c and in d the value b is stored in d because of the bracket.
Output:
$ g++ op3.cpp
$ a.out
5 6

7. What is the output of this program?

```
    #include <iostream>
```
```
    using namespace std;
```
```
    int main()
```
```
    {
```
```
        int i, j;
```
```
        j = 10;
```
```
        i = (j++, j + 100, 999 + j);
```
```
        cout << i;
```
```
        return 0;
```
```
    }
```

a) 1000
b) 11
c) 1010
d) 1001
View Answer

Answer: c
Explanation: j starts with the value 10. j is then incremented to 11. Next, j is added to 100. Finally, j (still containing 11) is added to 999 which yields the result 1010.
Output:
$ g++ op2.cpp
$ a.out
1010

8. What is the output of this program?

```
    #include <iostream>
```
```
    using namespace std;
```
```
    int main ()
```
```
    {
```
```
        int x, y;
```
```
        x = 5;
```
```
        y = ++x * ++x;
```
```
        cout << x << y;
```
```
        x = 5;
```
```
        y = x++ * ++x;
```
```
        cout << x << y;
```
```
        return 0;
```
```
    }
```

a) 749736
b) 736749
c) 367497
d) none of the mentioned
View Answer

Answer: a
Explanation: Because of the precedence the pre-increment and post increment operator, we got the output as 749736.
Output:
$ g++ op.cpp
$ a.out
749736

9. What is the output of this program?