01. SoftUni Reception

using System;

namespace SoftUniReception
{
    class Program
    {
        static void Main(string[] args)
        {
            int first = int.Parse(Console.ReadLine());
            int second = int.Parse(Console.ReadLine());
            int third = int.Parse(Console.ReadLine());
            int students = int.Parse(Console.ReadLine());
            int counter = 1, hours = 0;

            while (students > 0)
            {
                students -= first + second + third;
                hours += counter % 3 == 0 && students > 0 ? 2 : 1;
                counter += 1;
            }

            Console.WriteLine($"Time needed: {hours}h.\n");
        }
    }
}