using System;
using System.Text.RegularExpressions;
public class Test
{
public static void Main()
{
string s = "\t1.2.1 ";
Regex regex = new Regex(@"^[ \t][0-9]+(?:\.[0-9]+)*[ \t]");
if (regex.IsMatch(s)) {
Console.WriteLine("Match!");
}
}
}
dXNpbmcgU3lzdGVtOwp1c2luZyBTeXN0ZW0uVGV4dC5SZWd1bGFyRXhwcmVzc2lvbnM7CnB1YmxpYyBjbGFzcyBUZXN0CnsKCXB1YmxpYyBzdGF0aWMgdm9pZCBNYWluKCkKCXsKCQlzdHJpbmcgcyA9ICJcdDEuMi4xICI7CgkJUmVnZXggcmVnZXggPSBuZXcgUmVnZXgoQCJeWyBcdF1bMC05XSsoPzpcLlswLTldKykqWyBcdF0iKTsKCQkKCQlpZiAocmVnZXguSXNNYXRjaChzKSkgewoJCQlDb25zb2xlLldyaXRlTGluZSgiTWF0Y2ghIik7CQoJCX0KCX0KfQ==