[백준] 14235번 크리스마스 선물 (silver 3

import java.io.*;
import java.util.*;

public class Main{
    public static void main(String[] args)throws IOException{
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw=new BufferedWriter(new OutputStreamWriter(System.out));
        Queue<Integer> que=new PriorityQueue<>(Collections.reverseOrder());
        StringTokenizer st;
        int n=Integer.parseInt(br.readLine());
        for(int i=0; i<n; i++){
            st=new StringTokenizer(br.readLine());
            int temp=Integer.parseInt(st.nextToken());
            if(temp==0) {
                bw.write(que.isEmpty() ? "-1\n" : que.poll()+"\n");
            }
            else{
                for(int j=0; j<temp; j++){
                    que.offer(Integer.parseInt(st.nextToken()));
                }
            }

        }
        bw.flush();
    }
}