[Hard] 295. Find Median from Data Stream (Microsoft 기출 문제)

#문제 설명

#문제 풀이

class MedianFinder {
    PriorityQueue<Integer> minHeap = new PriorityQueue<>();
    PriorityQueue<Integer> maxHeap = new PriorityQueue<>(Collections.reverseOrder());
    
    public MedianFinder() {
    }
    public void addNum(int num) {
        maxHeap.offer(num);
        minHeap.offer(maxHeap.poll());
        if (minHeap.size() > maxHeap.size())
            maxHeap.offer(minHeap.poll());
    }
    public double findMedian() {
        if (maxHeap.size() > minHeap.size()) return maxHeap.peek();
        return (minHeap.peek() + maxHeap.peek()) / 2.0d;
    }
}