绝不重新定义继承而来的缺省参数值

#include "iostream"
using namespace std;
class base{
public:
virtual void fun(int i=1){
cout<<"base::"<<i<<endl;
}

};
class derive:public base
{
private:
virtual void fun(int i=2){
cout<<"derive::"<<i<<endl;
}
};
int main(int argc, char const *argv[])
{
base *test = new derive();
test->fun();//此时输出的i仍然是1,而不是derive里面的2
return 0;
}