c ++链表到跳转列表转换

Question

I want to convert a (simple linked) list into a skiplist which is derived from linked list. Inside the conversion ctor which gets a (linked-)list as param, i get a stackoverflow at *. I just call that ctor from main once. How is it possible that new SkipList is called loopwise?

class SkipList : public List {
public:     
    SkipList(SkipListEl* first) : List (first){};

    SkipList(const List& sl){                           
        ListEl* fst = sl.getFirst();
        new SkipList(fst);         // * <- stackoverflow

        while(fst->hasNext()){
            new SkipListEl(*fst);
            fst = fst->getNext();
        }
    };

Answer 1

You need to review your basic C++ rules on dynamic object creation. new calls the constructor for the object you're creating. By calling new object in the constructor for object , you're getting an infinite loop (infinite recursion, actually) leading to no more stack space.