using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var vertexCount = 5;

        var correct = CorrectNumer(vertexCount);

    }

    public static List<int> CorrectNumer(int count)

    {

        var correct = false;

        var random = new Random();

        var result = new int[count - 2];

        while (!correct)

        {

            Array.Clear(result, 0, count - 2);

            correct = true;

            var ids = GenerateList(count - 2, 3);

            var oIds = ids.OrderByDescending(i => i);

            foreach(var i in oIds)

            {

                if(i > 0)

                {

                    var maxIndex = (count - 2) - i;

                    var free = new List<int>();

                    for(var j = 0; j <= maxIndex; j++)

                    {

                        if(result[j] != 0)

                        {

                            free.Add(j);

                        }

                    }

                    if(free.Count > 0)

                    {

                        var index = random.Next(0, free.Count - 1);

                        result[free[index]] = i;

                    }

                    else 

                    {

                        correct = false;

                        break;

                    }

                }

            }

        }

        return result.ToList();

    }

    public static List<int> GenerateList(int count, int max)

    {

        var result = new List<int>();

        var random = new Random();

        for(var i = 0; i < count; i++)

        {

            result.Add(random.Next(max));

        }

        return result;

    }

}