[C/C++] Remind! Multiple-Inheritance of same-named-method from two classes.

See following example codes.

class A
{
public:
    virtual int a(void) {return 1; }
    virtual int b(void) {return 11;}
    int         c(void) {return 21;}
};

class B
{
public:
    virtual int a(void) {return 2; }
    virtual int b(void) {return 12;}
    int         c(void) {return 22;}
};

class C : public A, public B
{
public:
    virtual int a(void) { return 3; }
};

void main(void)
{
    C c;
    A* pa = &c;
    B* pb = &c;
    printf("%d / %d / %d\n", pa->a(), pb->a(), c.a()); // OK ---(*1)
    printf("%d\n", c.b());  // Compile Error due to ambiguous access ---(*2)
    printf("%d\n", c.c());  // Compile Error due to ambiguous access ---(*3)
}

In case of (*2) and (*3), Compiler gives ‘Error’ due to ambiguity – A::b()/B::b(). It’s clear.
But, there is no ambiguity in case (*1). Function ‘a’ is declared as ‘virtual’ in A and B. And ‘a’ also overridden in C. So, all three parameters of ‘printf’ means ‘C::a()’.

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