解法一：小根堆

堆的实现参见堆。通过不断找父节点打印路径。

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String[] input;
        input = reader.readLine().split(" ");
        final int N = Integer.parseInt(input[0]);
        final int M = Integer.parseInt(input[1]);
        input = reader.readLine().split(" ");
        Heap heap = new Heap();
        for (int i = 0; i < N; ++i) {
            heap.offer(Integer.parseInt(input[i]));
        }
        input = reader.readLine().split(" ");
        for (int i = 0; i < M; ++i) {
            int start = Integer.parseInt(input[i]);
            heap.printPath(start - 1);
        }
    }
}
class Heap {
    // 实际大小
    private int size;
    // 最大容量
    private int capacity;
    // 数据
    int[] data;
    /**
     * 初始化
     */
    public Heap() {
        size = 0;
        capacity = 1000;
        data = new int[capacity];
    }
    /**
     * 向上堆化
     *
     * @param i 起始位置
     */
    private void fixUp(int i) {
        int num = data[i];
        int father = (i - 1) / 2;
        while ((i > 0) && (data[father] > num)) {
            data[i] = data[father];
            i = father;
            father = (i - 1) / 2;
        }
        data[i] = num;
    }
    /**
     * 添加元素
     *
     * @param item 元素值
     */
    public void offer(int item) {
        // 扩容
        if (size == capacity) {
            data = Arrays.copyOf(data, data.length * 2);
            capacity *= 2;
        }
        data[size++] = item;
        fixUp(size - 1);
    }
    public void printPath(int start) {
        List<Integer> path = new ArrayList<>((int) (Math.log(size) / Math.log(2)));
        path.add(data[start]);
        while (start > 0) {
            start = (start - 1) / 2;
            path.add(data[start]);
        }
        for (int i = 0; i < path.size() - 1; ++i) {
            System.out.print(path.get(i) + " ");
        }
        System.out.println(path.get(path.size() - 1));
    }
}