using System;

using System.Text.RegularExpressions;

​

public class Program

{

    // numeric string with length = 8

    public static void Main()

    {

        string[] patterns = new string[]{"25_", "3__", "%4%"};

        Console.WriteLine("patterns: " + printArray(patterns));

        for (int i = 0; i < patterns.Length; i++)

        {

            // transform pattern

            patterns[i] = "^" + patterns[i].Replace("_", "[0-9]{1}").Replace("%", "[0-9]*") + "$";

        }

​

        Console.WriteLine("patterns: " + printArray(patterns));

        Console.WriteLine("");

        string[] candidates = new string[]{"12345678", "123", "", "-12341234", "asdf", "123412341234", "251", "30", "301", "4", "401", "456978573895", "4T"};

        for (int i = 0; i < candidates.Length; i++)

        {

            for (int k = 0; k < patterns.Length; k++)

            {

                Regex regex = new Regex(patterns[k]);

                Match match = regex.Match(candidates[i]);

                Console.WriteLine(candidates[i] + " matches pattern " + patterns[k] + ": " + match.Success);

            }

​

            Console.WriteLine("");

        }

    }

​

    private static string printArray(string[] arr)

    {

        return "{" + string.Join(",", arr) + "}";

    }

}