using System;
using System.Linq;
using System.Text.RegularExpressions;
public class Test
{
public static void Main()
{
var s = "This- -is - a test-sentence. -Test- --- One-Two--Three---Four----.";
var result = Regex.Replace(s, @"\b(-+)\b|-", "$1");
Console.WriteLine(result);
}
}
dXNpbmcgU3lzdGVtOwp1c2luZyBTeXN0ZW0uTGlucTsKdXNpbmcgU3lzdGVtLlRleHQuUmVndWxhckV4cHJlc3Npb25zOwoKcHVibGljIGNsYXNzIFRlc3QKewoJcHVibGljIHN0YXRpYyB2b2lkIE1haW4oKQoJewoJCXZhciBzID0gIlRoaXMtIC1pcyAtIGEgdGVzdC1zZW50ZW5jZS4gLVRlc3QtIC0tLSBPbmUtVHdvLS1UaHJlZS0tLUZvdXItLS0tLiI7CiAgICAJCXZhciByZXN1bHQgPSBSZWdleC5SZXBsYWNlKHMsIEAiXGIoLSspXGJ8LSIsICIkMSIpOwogICAgICAgCQlDb25zb2xlLldyaXRlTGluZShyZXN1bHQpOwoJfQp9