using System;
using System.Globalization;
using System.Collections.Generic;
using System.Linq;
 
public class Test
{
 
	public static void Main()
	{
        var list = new List<object> { "a", "b", "c", "d", "e", "a", "d" };
        for(int i=list.Count - 1; i >= 0; i--)
        {
           var obj = list[i];
           if(list.Take(i).Contains(obj))
               list.RemoveAt(i);
        }
 
      foreach(var obj in list)
            Console.WriteLine(obj);
	}
}

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