数据流中的第 K 大元素

/*
 * Problem: Design a class to find the kth largest element in a stream of integers using Java Streams.
 *
 * Solution:
 * - The logic remains similar to the non-stream implementation, using a min-heap.
 * - The difference is in initialization, where we utilize Java Streams to populate the heap.
 * - The add method is implemented similarly, checking the size of the heap and the value to be added.
 */
import java.util.PriorityQueue;
import java.util.stream.IntStream;

public class KthLargest {
    private PriorityQueue<Integer> minHeap;
    private int k;

    public KthLargest(int k, int[] nums) {
        this.k = k;
        this.minHeap = new PriorityQueue<>(k);
        // Use Streams to add initial elements
        IntStream.of(nums).forEach(this::add);
    }

    public int add(int val) {
        if (minHeap.size() < k) {
            minHeap.offer(val);
        } else if (val > minHeap.peek()) {
            minHeap.poll();
            minHeap.offer(val);
        }
        return minHeap.peek();
    }
}