using System;
using System.Collections.Generic;
using System.Linq;

namespace _02._Stack_Sum
{
    class Program
    {
        static void Main(string[] args)
        {
            var input = Console.ReadLine().Split().Select(int.Parse).ToArray();
            Stack<int> stack = new Stack<int>(input);
            var commandInfo = Console.ReadLine().ToLower();

            while (commandInfo != "end")
            {
                var tokens = commandInfo.Split();
                var command = tokens[0].ToLower();
                if (command == "add")
                {

                    int number1 = int.Parse(tokens[1]);
                    int number2 = int.Parse(tokens[2]);
                    stack.Push(number1);
                    stack.Push(number2);

                }
                else if (command == "remove")
                {
                    var countOfRemovedNums = int.Parse(tokens[1]);
                    if (stack.Count < countOfRemovedNums)
                    {
                        commandInfo = Console.ReadLine().ToLower(); // това тук е пропуснато
                        continue;
                    }

                    for (int i = 0; i < countOfRemovedNums; i++)
                    {
                        stack.Pop();
                    }
                }
                commandInfo = Console.ReadLine().ToLower();
            }
            var sum = stack.Sum();
            Console.WriteLine($"Sum: {sum}");
        }
    }
}