为什么加了这个const就能重载
iterator begin()
{
return iterator(head->next);
}
const_iterator begin()const
{
return const_iterator(head->next);
}
C++中允许const重载:
class People{
public:
int add(int a , int b){
return a - b;
}
int add(int a , int b)const{
return a + b;
}
};
People p = People(); p.add(5,4); -->结果为1
const People p = People(); p.add(5,4); -->结果为9
