parachute.txt

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Decrypt;

namespace Task1
{
    class Program
    {
        public const string data = "4.20 2\n0.53\n0.89";
        static void Main(string[] args)
        {
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_0.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_1.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_2.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_3.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_4.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_5.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_6.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_7.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_8.in");
            Calculation.Calculate(@"C:\Users\MirkoKojiRadi\Downloads\parachute\parachute_9.in");
            Console.ReadKey();
        }

        
    }
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Decrypt
{
    public class Calculation
    {
        public static void Calculate(string path)
        {
            System.IO.StreamReader file = new System.IO.StreamReader(path);

            string line = string.Empty;

            double totalRadiusOfSurface = 0;
            int numberOfIslands = 0;
            var counter = 0;
            double totalSurfaceOfIslands = 0;

            while ((line = file.ReadLine()) != null)
            {
                if (counter == 0)
                {
                    var tmp = line.Split(' ');
                    var radius = float.Parse(tmp[0]);
                    totalRadiusOfSurface = Math.PI * radius * radius;
                    numberOfIslands = int.Parse(tmp[1]);
                }
                else
                {
                    var tmp = float.Parse(line);
                    totalSurfaceOfIslands += Math.PI * (tmp * tmp);
                }
                counter++;
            }

            var result = Math.Round((totalRadiusOfSurface - totalSurfaceOfIslands) / totalRadiusOfSurface, 2);

            Console.WriteLine(result);
        }


    }
}