using System;
using System.Collections.Generic;
using System.Linq;
 
public class Test
{
	public static void Main()
	{
		            var results = new List<int>(){1,2,3,4,5,5,5,6,5,1};
            var dbResults = new List<int>();
            foreach (var element in results.Where(element => dbResults.Count == 0 || dbResults.Last() != element))
            {
                dbResults.Add(element);
            }
foreach(var res in dbResults)
{
 Console.WriteLine(res);
}
	}
}

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