using System;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		String miRuta1 = "C:\\Users\\JoseCarlos\\Desktop\\tmp3326\\tmp3326\\1.txt";
		Console.WriteLine(miRuta1);
		Console.WriteLine(Regex.Replace(miRuta1, "([^\\\\]+)\\\\\\1(?=\\\\[^\\\\]+$)", "$1\\CAMBIADO"));
 
		Console.WriteLine("---------------------------");
 
		String miRuta2 = "C:\\Users\\JoseCarlos\\Desktop\\mv\\lolo-s001.vmdk";
		Console.WriteLine(miRuta2);
		Console.WriteLine(Regex.Replace(miRuta2, "([^\\\\]+)\\\\\\1(?=\\\\[^\\\\]+$)", "$1\\CAMBIADO"));
	}
}

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