阅读程序，写出运行时输出的结果

#include using namespace std; class A{public:
A0{cout<<"constructing A"<AO{cout<<"destructing A"<class B: public A(public:
BO{cout<<"constructing B"<BO){cout<<"destructing B"<class C: public B{public:
CO{cout<<"constructing C"<int mainO{C cl; retum 0;)

这些带删除线的字符是怎么回事？
格式化一下输入代码，太乱了

服了