Operator Overloading Interview Questions Mock Test

Question 1: C++ OOPS Operator Overloading Concept

Which operators cannot be overloaded in C++?

Question 2: C++ OOPS Operator Overloading Return Type

What should be the return type when overloading the ++ operator (prefix version)?

Question 3: C++ OOPS Unary Operator Overloading Example

What will be the output?

#include <iostream>
using namespace std;
class Counter {
    int value;
public:
    Counter(int v) : value(v) {}
    void operator++() { value++; }
    void display() { cout << value; }
};
int main() {
    Counter c(5);
    ++c;
    c.display();
}

Question 4: C++ OOPS Binary Operator Overloading

Which function signature correctly overloads the binary + operator inside a class Complex?

Question 5: C++ OOPS Friend Function Operator Overloading

What will be the output?

#include <iostream>
using namespace std;
class Complex {
    int x;
public:
    Complex(int v) : x(v) {}
    friend Complex operator+(Complex c1, Complex c2);
    void show() { cout << x; }
};
Complex operator+(Complex c1, Complex c2) {
    return Complex(c1.x + c2.x);
}
int main() {
    Complex a(3), b(4);
    Complex c = a + b;
    c.show();
}

Question 6: C++ OOPS Operator Overloading Limitation

Which of the following statements is NOT true?

Question 7: C++ OOPS Overloading Postfix ++

Which is the correct function signature for overloading postfix ++?

Question 8: C++ OOPS Relational Operator Overloading

What will be the output?

#include <iostream>
using namespace std;
class Box {
    int volume;
public:
    Box(int v) : volume(v) {}
    bool operator>(Box b) { return volume > b.volume; }
};
int main() {
    Box b1(10), b2(20);
    cout << (b1 > b2);
}

Question 9: C++ OOPS Overloading [] Operator

Which statement about overloading [] is correct?

Question 10: C++ OOPS Operator Overloading Example (Mix)

What will be the output?

#include <iostream>
using namespace std;
class Point {
    int x;
public:
    Point(int v) : x(v) {}
    Point operator-(Point p) { return Point(x - p.x); }
    void show() { cout << x; }
};
int main() {
    Point p1(10), p2(3);
    Point p3 = p1 - p2;
    p3.show();
}