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.
Example 1: Input: [3,2,1,5,6,4] and k = 2 Output: 5 Example 2: Input: [3,2,3,1,2,4,5,5,6] and k = 4 Output: 4
Note: You may assume k is always valid, 1 ≤ k ≤ array's length.
See the full details of the problem Kth Largest Element in an Array at LeetCode