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CSharp · Console

/Program.cs

using System;
using System.Text.RegularExpressions;
					
public class Program
{
	public static void Main()
	{
		String sample = "deqn1-2";
        Regex regex = new Regex("deqn(?:(?<match1>\\d+)-(?<match2>\\d+)|(?<match1>\\d+\\w+)-(?<match2>\\d+\\w+))\\b");

        Match match = regex.Match(sample);

        if (match.Success)
        {
            Console.WriteLine(match.Groups["match1"].Value);
			Console.WriteLine(match.Groups["match2"].Value);
        }
	}
}