# 215. Kth Largest Element in an Array

Find the **k**th 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.

#### 解题要点：

用priority queue来做，保持pq的size为k，如果一旦大于k，将顶层poll出去。最后返回pq.poll()顶层的值。

#### Python：

```python
class Solution(object):
    def findKthLargest(self, nums, k):
        """
        :type nums: List[int]
        :type k: int
        :rtype: int
        """
        return heapq.nlargest(k, nums)[-1]
```

#### Java：

```java
class Solution {
    public int findKthLargest(int[] nums, int k) {
        PriorityQueue<Integer> pq = new PriorityQueue<>();
        for(int n : nums){
            pq.add(n);
            if(pq.size() > k) pq.poll();
        }
        return pq.poll();
    }
}
```

```java
class Solution {
    public int findKthLargest(int[] nums, int k) {
        Arrays.sort(nums);
        return nums[nums.length - k];
    }
}
```