HW-5.3

using System;
using System.Collections.Generic;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            bool exit = false;
            List<int> nums = new List<int>();
            while (!exit)
            {
                string input = Console.ReadLine();
                switch (input)
                {
                    case "exit":
                        exit = true;
                        break;
                    case "sum":
                        int sum = 0;
                        foreach (var num in nums)
                        {
                            sum += num;
                        }

                        Console.WriteLine("Сумма всех веденных чисел: " + sum);
                        break;
                    default:
                        nums.Add(Convert.ToInt32(input));
                        break;
                }
            }
        }
    }
}