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

class Solution {
    public int findKthLargest(int[] nums, int k) {
         PriorityQueue<Integer> pq = new PriorityQueue<>();//优先级队列
        for(int i:nums){
            pq.add(i);
            if(pq.size()>k){
                pq.poll();//删除头指针所指
            }
        }
        return pq.peek();//指向头，不上
    }
}