using System;

using System.Collections.Generic;

using System.Linq;

​

namespace MaximumElement

{

    public class MaximumElement

    {

        public static void Main()

        {

            int n = int.Parse(Console.ReadLine());

            Stack<int> stack = new Stack<int>();

            int biggestNum = int.MinValue;

​

            for (int i = 0; i < n; i++)

            {

                string[] command = Console.ReadLine().Split();

​

                if (command[0].Equals("1"))

                {

                    int num = int.Parse(command[1]);

                    stack.Push(num);

​

                    if (num > biggestNum)

                    {

                        biggestNum = num;

                    }

                }

                else if (command[0].Equals("2"))

                {

                    stack.Pop();

​

                    if (stack.Count > 0)

                    {

                        biggestNum = stack.Max();

                    }

                }

                else if (command[0].Equals("3"))

                {

                    Console.WriteLine(biggestNum);

                }

            }

        }

    }

}

​