[LeetCode] 215. Kth Largest Element in an Array

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.

class Solution {
    public int findKthLargest(int[] nums, int k) {
        PriorityQueue<Integer> queue = new PriorityQueue<>();
        
        for (int num : nums) {
            queue.offer(num);
            if (queue.size() > k) {
                queue.poll();
            }
        }
        
        return queue.peek();
    }
}

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

 

PriorityQueue()

Creates a PriorityQueue with the default initial capacity (11) that orders its elements according to their natural ordering.

natural ordering: 1 2 3 4 5 6 7 10 11 12 20 21 (reference)