using System;

namespace ConsoleApp7
{
    internal class Program
    {
        static void Main(string[] args)
        {
            double x = Convert.ToDouble(Console.ReadLine());

            while (Math.Abs(x) > 1)
            {
                Console.Write($"x value isn’t in the interval.Input value on interval(-1; 1): ");
                x = Convert.ToDouble(Console.ReadLine());
            }

            double s = 1;
            double cur_num = x;
            for (int i = 2; cur_num >= 0.0001; i += 2)
            {
                double loc_num = x;
                for (int n = 1; n < i; n++)
                {
                    loc_num *= x;
                }
                s += loc_num;
                cur_num = loc_num;
            }
            Console.WriteLine($"s == {s}");
        }
    }
}