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CSharp · Console

/Program.cs

using System;
using System.Text.RegularExpressions;
					
public class Program
{
	public static void Main()
	{
		Regex regex = new Regex(@"(?msi)(?:(\s*/\*.*?\*/)|(([a-z0-9#. \[\]=\"":_-]+)\s*(?:,\s*|{))+(?:(\s*/\*.*?\*/)|(?:\s*([a-z0-9 -]+\s*):\s*([a-z0-9#,<>\?%. \(\)\\\/\*\{\}:'\""!_=-]+);?))*\s*})");
		var regexMatch = regex.Match("   a, abbr, acronym, address, applet, article, aside, audio, b, big, blockquote, body, canvas, caption, center, cite, code {");
		Console.WriteLine(regexMatch.Captures.Count);
	}
}