//Rextester.Program.Main is the entry point for your code. Don't change it.

//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

​

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text.RegularExpressions;

​

namespace Rextester

{

    public class Program

    {

        public static void Main(string[] args)

        {

            List<string> values = new List<string>() { "(1,1,1)", "(1,2,1)", "(1,4,1)", "(2,3,2)", "(2,5,2)", "(1,4,2)", "(1,2,2)", "(1,1,2)", "(2,5,1)", "(2,4,1)", "(2,9,1)" };

            List<Vector3> vectors = values.Select(v => new Vector3(v)).ToList();

            var result = vectors

                .GroupBy(v => Tuple.Create(v.X, v.Z))

                .Select(vg => vg.OrderByDescending(v => v.Y).First())

                .ToList();

            foreach (var val in result)

            {

                Console.Write(val.ToString() + " ");

            }

            Console.WriteLine();

        }

    }

    public class Vector3

    {

        public int X {get;set;}

        public int Y {get;set;}

        public int Z {get;set;}

        public Vector3()

        {