思路

使用Java的大顶堆（PriorityQueue）

Code

import java.util.ArrayList;
import java.util.PriorityQueue;
public class Solution {
    public ArrayList<Integer> maxInWindows(int [] num, int size)
    {
        ArrayList<Integer> ret = new ArrayList<>();
        if(num == null || num.length == 0 || size <= 0|| size > num.length)
            return ret;
        //大顶堆
        PriorityQueue<Integer> queue = new PriorityQueue<>((o1,o2)->(o2-o1));
        for(int i = 0; i < size; i++)
        {
            queue.add(num[i]);
        }
        ret.add(queue.peek());
        for(int i = size; i < num.length ; i++)
        {
            queue.remove(num[i-size]);
            queue.add(num[i]);
            ret.add(queue.peek());
        }
        return ret;
    }
}