Hello! I`ve got a code, equations must be right, but the result is different from sample. I don`t know what the problem is. Please, help!! My result is 45,28, whereas the sample`s one is 52,04.

static void Main(string[] args)
        {
            const double D = 6875;
            const double pi = 3.1415926535897932384626433;
            string trash;
            char[] separators = new[] { ' ', '^', '"', '\''};
            /* double shipx, shipy, shipz, icex, icey, icez; */
            for (int i = 0; i < 3; i++)
                trash = Console.ReadLine();
            var shipLat = Console.ReadLine().Split(separators);
            var shipLong = Console.ReadLine().Split(separators);
            trash = Console.ReadLine();
            var iceLat = Console.ReadLine().Split(separators);
            var iceLong = Console.ReadLine().Split(separators);
            trash = Console.ReadLine();

            double phi1 = (int.Parse(shipLat[0]) + (int.Parse(shipLat[1]) + int.Parse(shipLat[2]) / 60) / 60) * (pi / 180);
            double phi2 = (int.Parse(shipLong[1]) + (int.Parse(shipLong[2]) + int.Parse(shipLong[3]) / 60) / 60) * (pi / 180);
            if (shipLat[3] == "SL") phi1 = -phi1;
            if (shipLong[4] == "WL") phi2 = -phi2;

            double L1 = (int.Parse(iceLat[0]) + (int.Parse(iceLat[1]) + int.Parse(iceLat[2]) / 60)/60) * (pi / 180);
            double L2 = (int.Parse(iceLong[1]) + (int.Parse(iceLong[2]) + int.Parse(iceLong[3]) / 60)/60) * (pi / 180);
            if (iceLat[3] == "SL") L1 = -L1;
            if (iceLong[4] == "WL") L2 = -L2;

            double ans = Math.Acos(Math.Sin(phi1) * Math.Sin(L1) + Math.Cos(phi1) * Math.Cos(L1) * Math.Cos(L2-phi2));
            double dist = ans * D/2;

            Console.Write("The distance to the iceberg: ");
            Console.WriteLine("{0:0.00}", dist);
            if (100.00 - dist > 0.005) Console.WriteLine("DANGER!");
        }

The problem is solved. It`s impossible to have the right answer with INT parsing. You need to use double.