Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element.
For example,
Given [3,2,1,5,6,4] and k = 2, return 5.
解题思路：
本题是《算法导论》原题，
Java for LeetCode 215 Kth Largest Element in an Array【Coming Soon】
原文：http://www.cnblogs.com/tonyluis/p/4564601.html