剑指offer(牛客网) 最小的K个数

import java.util.ArrayList;
import java.util.PriorityQueue;
public class Solution {
    public ArrayList GetLeastNumbers_Solution(int [] arr, int k) {
        if(k > arr.length) {
            return new ArrayList();
        }
        ArrayList list = new ArrayList();
		PriorityQueue queue = new PriorityQueue<>();
		for(int i = 0; i < arr.length; i++) {
			queue.offer(arr[i]);
		}
		for(int i = 0; i < k; i++) {
			list.add(queue.poll());
		}
		return list;
    }
}