using System;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(ExtractNumbers("SM150954"));

        Console.WriteLine(ExtractNumbers("SM-150954"));

        Console.WriteLine(ExtractNumbers("S10M150954"));

        Console.WriteLine(ExtractNumbers("SM10-150954"));

    }

    static string ExtractNumbers(string input)

    {

        Match match = Regex.Match(input, @"\d+$"); // Find numbers at the end

        return match.Success ? match.Value : "";

    }

}