using System;
using System.Collections.Generic;
using System.Text.RegularExpressions;
using System.Linq;
 
public class Test
{
	public static void Main()
	{
		var s = "&RPork && Beans&CDocument Title";
		var result = Regex.Split(s, "(&[LRC])")
			.Where(x => !string.IsNullOrWhiteSpace(x))
			.ToList();
		var data = result.Where((c,i) => i % 2 == 0).Zip(result.Where((c,i) => i % 2 != 0),
			(delimiter, value) => new KeyValuePair<string, string>(delimiter, value));
		foreach (var kvp in data)
			Console.WriteLine("Delimiter: {0}\nValue: {1}", kvp.Key, kvp.Value);
	}
}

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