[问题] Google Interview Question (3)

楼主: RockLee (Now of all times)   2013-02-13 18:17:31
原始网址:
http://www.careercup.com/question?id=15381730
题目:
Given a 2 dimensional (R*C) array. The rows and columns are sorted.
Find the Kth largest element from the 2-d array in most efficient way.
Can it be done in-place?
我能想到最快的方法是用 Balanced Tree (Ex. TreeMap in Java) 来解,
Time Complexity: O(K*logK).
要 in-place 来解我只有想到 in-place merge sort,
Time Complexity: O((R*C)*log(R*C)).
不过 in-place merge sort 完全没用到 The rows and columns are sorted 这件事,
应该不会是一个好的答案.
不知道是否有比 O(K*logK) 更快的方法?
或是比较合理的 in-place 解法?
作者: singlovesong (~"~)   2013-02-13 20:14:00
想必跟1d 的case 有关系 !
作者: FRAXIS (喔喔)   2013-02-13 21:17:00
楼主: RockLee (Now of all times)   2013-02-13 22:30:00
感谢F大的连结 等明天精神好再来读paper
作者: yoco315 (眠月)   2013-02-16 13:16:00
感觉也是 median 的变形 ... @@
作者: FRAXIS (喔喔)   2013-02-17 11:37:00
技巧类似,只是稍微复杂些。

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