Kth Largest Element in a Stream

找一个流中第k大的元素. 找大用min heap.

class KthLargest {
    PriorityQueue<Integer> m;
    int k;
    public KthLargest(int k, int[] nums) {
        this.k = k;
        m = new PriorityQueue<>();
        for(int n : nums)
            m.add(n);
    }
    
    public int add(int val) {
        m.add(val);
        while(m.size() > k) {
            m.poll();
        }
        return m.peek();
    }
}