class Program
    {
        static void Main(string[] args)
        {
            var inputs = File.ReadAllLines("input.txt").Select(line => int.Parse(line));
            Console.WriteLine($"Part 1: Total fuel required is {inputs.Sum(FuelRequired)}");
            Console.WriteLine($"Part 2: Total fuel required is {inputs.Sum(TotalFuelRequired)}");
        }

        static int TotalFuelRequired(int mass)
        {
            var fuel = FuelRequired(mass);
            return fuel == 0 ? 0 : fuel + TotalFuelRequired(fuel);
        }

        static int FuelRequired(int mass) => Math.Max((mass / 3) - 2, 0);
    }