C++ 基础题目，分析输出结果解释
#include <iostream.h>
class A{
public:
virtual void printMe(){cout<<"This is class A printing. "<<endl;};
} ;

class B:public A{
public:
void printMe() {cout << "This is class B printing. "<<endl;}
} ;
class C:public B{
public:
void printMe() {cout <<"This is class C printing. "<<endl;}
} ;

void print(A a){
a.printMe();
}
int main(){
B b;
C c;
print(b);
print(c);
return 0;
}

为什么输出的是
This is class A printing.
This is class A printing.

而不是
This is class B printing.
This is class C printing.
呢？ 不是放了virtual 了？
生成A的临时对象
[解决办法]

生成A的临时对象

[解决办法]

引用:

虚函数只在使用指针或引用调用的时候生效
void print(A a)这种参数将把输入的B b和C c复制成局部的A a，再由对象a调用A::printMe()

正解，要想获得多态情况的输出，可以改成这样void print(A& a)