using System;
using System.IO;
using System.Text.RegularExpressions;
public class Test
{
public static void Main()
{
var str = "AB12 (1,2,3 words, 4,5,6,7,8,9)";
var pat = @"(?<=^[A-Z]{2}\d{2}\s+\([^()]*)\s*[^,\d]+(?=[^()]*\))";
var res = Regex.Replace(str, pat, string.Empty);
Console.WriteLine(res);
}
}
dXNpbmcgU3lzdGVtOwp1c2luZyBTeXN0ZW0uSU87CnVzaW5nIFN5c3RlbS5UZXh0LlJlZ3VsYXJFeHByZXNzaW9uczsKCnB1YmxpYyBjbGFzcyBUZXN0CnsKCXB1YmxpYyBzdGF0aWMgdm9pZCBNYWluKCkKCXsKCQl2YXIgc3RyID0gIkFCMTIgKDEsMiwzIHdvcmRzLCA0LDUsNiw3LDgsOSkiOwoJCXZhciBwYXQgPSBAIig/PD1eW0EtWl17Mn1cZHsyfVxzK1woW14oKV0qKVxzKlteLFxkXSsoPz1bXigpXSpcKSkiOwoJCXZhciByZXMgPSBSZWdleC5SZXBsYWNlKHN0ciwgcGF0LCBzdHJpbmcuRW1wdHkpOwoJCUNvbnNvbGUuV3JpdGVMaW5lKHJlcyk7Cgl9Cn0=