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CSharp · Console

/Program.cs

using System;
using System.Text.RegularExpressions;
					
public class Program
{
	public static void Main()
	{
		string[] commands = 
		{
			"{AA00:00;|}",
			"{ABC0:93;||}",
			"{AAB08:02;|}",
			"{123AA:AA;|}",
			"{AA123,123:123,123;|}"
		};
		
		foreach (string command in commands)
		{
			if (Regex.Match(command, "^{[A-Z]+\\d+:\\d+;\\|}$").Success)
			{
				Console.WriteLine("Good command");
			}
			else 
			{
				Console.WriteLine("Bad command");
			}
		}
	}
}