using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        string input = "17.644886;87.427452;51.513859;121.296410;+0.481;;89.176285;47.627792;123.045242;81.496758;+0.524;;";

        var output1 = input.Split(new[] { ";;" }, StringSplitOptions.RemoveEmptyEntries).Select(s => s.Split(';')).ToArray();

        foreach (var item in output1[0])

        {

            Console.WriteLine(Math.Round(Convert.ToDouble(item), 2));

        }

​

​

    }

}