C++ OOPs Concepts Test 4

What is true about constructors in C++?

Which of the following is true about destructors in C++?

Which is the correct way to write a getter for salary (private) in class Employee?

Which keyword is used to solve the diamond problem in C++?

How do we declare a pure virtual function?

Can an abstract class in C++ have normal (non-virtual) functions?

What will be the output?

#include <iostream>
using namespace std;
class Number {
    int value;
public:
    Number(int v) { value = v; }
    friend int getValue(Number n);
};
int getValue(Number n) {
    return n.value;
}
int main() {
    Number n(42);
    cout << getValue(n);
}

Which of the following is NOT allowed in static member functions?

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

How is V-Table affected in multiple inheritance?

Which symbol is used before the class name to define a destructor?

Which is the correct way to define a destructor for class `Car`?

Which is the best way to define a setter for salary in class Employee?

In inheritance, what is the order of constructor calls?

What will be the output?

#include<iostream>
using namespace std;
class Shape {
public: virtual void draw() = 0; };
class Circle : public Shape {
public: void draw() { cout << "Circle"; } };
int main() {
    Circle c; c.draw();
}

Which of the following is true about pure virtual functions?

Which of the following is true?

What will be the output?

#include <iostream>
using namespace std;
class Demo {
    static int x;
public:
    Demo() { x++; }
    ~Demo() { x--; }
    static int getX() { return x; }
};
int Demo::x = 0;
int main() {
    Demo d1, d2;
    cout << Demo::getX();
}

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);
}

Why should destructors be declared virtual in base classes?