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分享为什么forward_list不支持push_back
为什么forward_list不支持push_back而list支持呢，标准库容器这样设计是什么道理啊
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zybjtu 2014-05-14
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说错了，forward_list 查到链表尾部是O(n)复杂度。 因为要从链表头出发，寻找到链表尾
zybjtu 2014-05-14
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list 是由双向链表实现的。只要记录尾指针便可以O(1)插入删除。
forward_list 顾名思义，是单链表实现的，不构成环的话，有去无回。每次从链表头插入需要O(n)复杂度
ri_aje 2014-05-14
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标准自己说了原因：
c++11 23.3.4.1/1
[Note: It is intended that forward_list have zero space or time overhead relative to a hand-written C-style singly linked list. Features that would conflict with that goal have been omitted. — end note]
mujiok2003 2014-05-13
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因为单向链表实现push_back效率不高(复杂度为O(n)), 而双向链表的push_back复杂度为O(1)。
rmaly 2014-05-13
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应该是内部数据结构是会有排序的，所以push_back毫无意义
merlinfang 2014-05-11
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Forward list is a container which supports fast insertion and removal of elements from anywhere from the container. Fast random access is not supported. It is implemented as singly-linked list and essentially does not have any overhead compared to its implementation in C. Compared to std::list this container provides more space efficient storage, when bidirectional iteration is not needed.
