#pragma warning disable

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text;
using System.Text.RegularExpressions;
using System.Diagnostics;
using System.Numerics;
using System.Collections;
using System.Timers;

static class MainClass
{
    public static void Main(string[] args)
    {
        var pq = new PriorityQueue<int>();
        while (true)
        {
            var message = Console.ReadLine().SplittedStringToList();
            if (message[0] == "insert")
            {
                var item = message[1].ToInt32();
                pq.Push(item);

            }
            else if (message[0] == "extract")
            {
                Console.WriteLine(pq.Pop());
            }
            else
            {

                Console.ReadLine();
                return;
            }
        }
    }

    class PriorityQueue<T>
      where T : IComparable<T>
    {
        List<T> buffer;

        public PriorityQueue() { buffer = new List<T>(); }
        public PriorityQueue(int capacity) { buffer = new List<T>(capacity); }

        static void PushHeap(List<T> array, T elem)
        {
            int n = array.Count;
            array.Add(elem);

            while (n != 0)
            {
                int i = (n - 1) / 2;
                if (array[n].CompareTo(array[i]) > 0)
                {
                    T tmp = array[n]; array[n] = array[i]; array[i] = tmp;
                }
                n = i;
            }
        }


        static void PopHeap(List<T> array)
        {
            int n = array.Count - 1;
            array[0] = array[n];
            array.RemoveAt(array.Count - 1);

            for (int i = 0, j; (j = 2 * i + 1) < n;)
            {
                if ((j != n - 1) && (array[j].CompareTo(array[j + 1]) < 0))
                    j++;
                if (array[i].CompareTo(array[j]) < 0)
                {
                    T tmp = array[j]; array[j] = array[i]; array[i] = tmp;
                }
                i = j;
            }
        }


        public void Push(T elem)
        {
            PushHeap(this.buffer, elem);
        }


        public T Pop()
        {
            var data = buffer[0];
            PopHeap(buffer);
            return data;
        }

        public int Count
        {
            get { return buffer.Count; }
        }
    }

    #region ライブラリ
    public static long ToInt64(this string str) => long.Parse(str);
    public static int ToInt32(this string str) => int.Parse(str);
    public static BigInteger ToBigInteger(this string str) => BigInteger.Parse(str);
    public static List<string> SplittedStringToList(this string str) => str.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).ToList();
    public static List<int> SplittedStringToInt32List(this string str) => str.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).Select(x => int.Parse(x)).ToList();
    public static List<BigInteger> SplittedStringToBigInteger(this string str) => str.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).Select(x => BigInteger.Parse(x)).ToList();

    public const int INF = int.MaxValue / 2;
    #endregion
}



Measured memory_bytes: 25912