C++重载、重写、重定义

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#include <iostream>

#include <complex>

usingnamespacestd;

classBase

{

public:

virtualvoida(intx) { cout <<"Base::a(int)"<< endl; }

// overload the Base::a(int) function

virtualvoida(doublex) { cout <<"Base::a(double)"<< endl; }

virtualvoidb(intx) { cout <<"Base::b(int)"<< endl; }

voidc(intx) { cout <<"Base::c(int)"<< endl; }

};

classDerived :publicBase

{

public:

// redefine the Base::a() function

voida(complex<double> x) { cout <<"Derived::a(complex)"<< endl; }

// override the Base::b(int) function

voidb(intx) { cout <<"Derived::b(int)"<< endl; }

// redefine the Base::c() function

voidc(intx) { cout <<"Derived::c(int)"<< endl; }

};

intmain()

{

Base b;

Derived d;

Base* pb =newDerived;

// ----------------------------------- //

b.a(1.0);// Base::a(double)

d.a(1.0);// Derived::a(complex)

pb->a(1.0);// Base::a(double), This is redefine the Base::a() function

// pb->a(complex<double>(1.0, 2.0)); // clear the annotation and have a try

// ----------------------------------- //

b.b(10);// Base::b(int)

d.b(10);// Derived::b(int)

pb->b(10);// Derived::b(int), This is the virtual function

// ----------------------------------- //

deletepb;

return0;

}