Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
1.将prev改成shared_ptr类型,防止首尾指针互相指向,无法释放
2.给Node的构造函数添加explicit防止隐式构造,并且使用初始化列表减少一次赋值。
3.用两个指针实现深拷贝
4.为什么删除拷贝赋值函数也不出错? 因为编译器默认使用析构函数+拷贝构造来代替拷贝赋值函数
5.print函数处:有什么值得改进的?传参const List&,减少拷贝并提高运行速度,减少运行时内存占用