问一道FB design之后续# JobHunting - 待字闺中
n*y
1 楼
原帖在这里： http://www.mitbbs.com/article_t1/JobHunting/33285661_0_1.html
今天跟FB专门做privacy setting一美国大牛又聊到了这个问题，跟他讲了之前大家讨
论的“post to friends' timeline”的想法。他的回复是：
This can be done simpler, without any extra writes.
A hint: You are thinking about the problem as "How to check if C is a friend
of friends of A". But it is possible to rephrase the question in an other
way which will make the problem much simpler to solve.
大家怎么看？
PS： 再把题目贴一下
privacy setting. 说是每个user有一个friend
list, user可以发Post, 问如何设计Ouser friends的friends可见,时间复杂度O(N)
今天跟FB专门做privacy setting一美国大牛又聊到了这个问题，跟他讲了之前大家讨
论的“post to friends' timeline”的想法。他的回复是：
This can be done simpler, without any extra writes.
A hint: You are thinking about the problem as "How to check if C is a friend
of friends of A". But it is possible to rephrase the question in an other
way which will make the problem much simpler to solve.
大家怎么看？
PS： 再把题目贴一下
privacy setting. 说是每个user有一个friend
list, user可以发Post, 问如何设计Ouser friends的friends可见,时间复杂度O(N)