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C++ | Inheritance | Question 1

#include<iostream>    using namespace std; class Base1 {  public:      Base1()      { cout << " Base1's constructor called" << endl;  } };    class Base2 {  public:      Base2()      { cout << "Base2's constructor called" << endl;  } };    class Derived: public Base1, public Base2 {    public:      Derived()      {  cout << "Derived's constructor called" << endl;  } };    int main() {    Derived d;    return 0; } OPTIONS: (A) Compiler Dependent (B) Base1′s constructor called Base2′s constructor called Derived’s constructor called (C) Base2′s constructor called Base1′s constructor called Derived’s constructor called (D) Compiler Error ANSWER: Answer: (B)  Explanation: When a class inherits from multiple classes, constructors of base classes are called in the same order as they are specified in inheritance. C++ | Inheritance | Question 2 #include<iostream> using namespace std; class Base { public:     void show()     {         cout<<" In Base ";     } }; class Derived: public Base { public:     int x;     void show()     {         cout<<"In Derived ";     }     Derived()     {         x = 10;     } }; int main(void) {     Base *bp, b;     Derived d;     bp = &d;     bp->show();     cout << bp->x;        return 0; } OPTIONS: (A) Compiler Error in line ” bp->show()” (B) Compiler Error in line ” cout << bp->x” (C) In Base 10 (D) In Derived 10 Answer: (B)  Explanation: A base class pointer can point to a derived class object, but we can only access base class member or virtual functions using the base class pointer. C++ | Inheritance | Question 3 #include<iostream> using namespace std; class Base1 { public:     char c; }; class Base2 { public:     int c; }; class Derived: public Base1, public Base2 { public:     void show()  { cout << c; } }; int main(void) {     Derived d;     d.show();     return 0; } OPTIONS: (A) Compiler Error in “cout << c;" (B) Garbage Value (C) Compiler Error in “class Derived: public Base1, public Base2″ Answer: (A) Explanation: The variable ‘c’ is present in both super classes of Derived. So the access to ‘c’ is ambiguous. The ambiguity can be removed by using scope resolution operator. #include<iostream> using namespace std; class Base1 { public:     char c; }; class Base2 { public:     int c; }; class Derived: public Base1, public Base2 { public:     void show()  { cout << Base2::c; } }; int main(void) {     Derived d;     d.show();     return 0; }