Recently I came across a question asked by wang2191195 on a Chinese IT forum CSDN which asks about a C++ program puzzle. He has a code snippet which cannot be compiled. The code is:#include <cstdlib>#include <iostream>using namespace std;class Base{public: virtual void func(){ cout << "Base::func()" << endl; } virtual int func( int num ){ cout << "Base::func( int " << num << " )" << endl; return 0; }};class Derived : public Base{public: virtual void func(){ cout << "Derived::func()" << endl; ...