using System;

public class Program

{

    public static void Main()

    {

        var label = "3.3-2020-09123-cenas";

        var label2 = "3.3";

​

​

        Console.WriteLine($"Feature name: {GetFeatureName(label)}");

        Console.WriteLine($"Feature name: {GetFeatureName(label2)}");

​

    }

    private static string GetFeatureName(string branchName)

    {

        var hyphenIndex = branchName.IndexOf('-');

        return hyphenIndex > 0 ? branchName.Substring(hyphenIndex) : string.Empty;

    }

}