---

using System;

namespace ConsoleApp1
{
    internal class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Введите значения a и b");

            Console.Write("a = ");
            double a = double.Parse(Console.ReadLine());

            Console.Write("b = ");
            double b = double.Parse(Console.ReadLine());

            double maximum = Math.Max(a * 2, b);
            double minimum = Math.Min(a, b * 4);

            if (minimum <= 0)
            {
                Console.WriteLine("Ошибка: значение minimum должно быть больше 0.");
                return;
            }

            double numerator = maximum - 10 * Math.Sqrt(minimum) + 4.2 * minimum;
            double denominator = 1 + (2 * maximum) / minimum;

            double result = numerator / denominator;

            Console.WriteLine($"max(2a, b) = {maximum}");
            Console.WriteLine($"min(a, 4b) = {minimum}");
            Console.WriteLine($"d = {result}");

            Console.ReadKey();
        }
    }
}