using System;

using System.Collections.Generic;

public class Program

    {

        public static void Main(string[] args)

        {

            int nTeams = 12;

            Program prg = new Program();

            prg.PrepareMatches(nTeams);

            Console.ReadLine();

        }

        private void PrepareMatches(int nTeams)

        {

            ITournament trmnt = new ProKabaddiTournament();

​

            ITournament trmntWithCons = new ProKabaddiTournamentWithConstraints();

​

            List<Match> baseMatches = trmnt.PrepareMatches(nTeams);

​

            trmntWithCons.BaseTournament = baseMatches;

            List<Match> matches = trmntWithCons.PrepareMatches(nTeams);

​

            foreach (Match mth in matches)

            {

                Console.WriteLine(mth.MatchName + "  MatchDay_@Home: " + mth.MatchDayHome + "  MatchDay_@Away: " + mth.MatchDayAway);

            }

        }

​

​

        public class Match

        {

            public string MatchName { get; set; }

            public int MatchDayHome { get; set; }

            public int MatchDayAway { get; set; }

            public int TeamA { get; set; }

            public int TeamB { get; set; }

            public DateTime MatchDateHome { get; set; }

            public DateTime MatchDateAway { get; set; }

            public string MatchLocationHome { get; set; }

            public string MatchLocationAway { get; set; }

        }

        public interface ITournament

        {

            List<Match> BaseTournament { get; set; }

            List<Match> PrepareMatches(int nTeams);

        }

        public class ProKabaddiTournament : ITournament

        {

            private List<Match> sch;

            public List<Match> BaseTournament

            { get { return sch; } set { sch = value; } }

            public List<Match> PrepareMatches(int nTeams)

            {

                sch = new List<Match>();

                DrawMatches(nTeams);

                RemoveDummyTeamMatch(nTeams, ref sch);

                return sch;

            }

            private void RemoveDummyTeamMatch(int nTeams, ref List<Match> matches)

            {

                int teams = (nTeams % 2 == 1 ? nTeams + 1 : nTeams);

                if (teams > nTeams) //there is a dummy team. We have to remove all matches of the last team.

                {

                    string dummyTeam = "Team" + teams.ToString();

​

                    matches.RemoveAll(m => m.MatchName.Contains(dummyTeam) == true);

                }

            }

            private void DrawMatches(int nTeams)

            {

                int teams = (nTeams % 2 == 1 ? nTeams + 1 : nTeams);

​

                string[] sideA = new string[teams / 2];

                string[] sideB = new string[teams / 2];

                int y = 0;

                for (int i = 0; i < teams; i = i + 2)

                {

                    sideA[y] = "Team" + (i + 1).ToString();

                    sideB[y] = "Team" + (i + 2).ToString();

                    y++;

                }

​

                for (int i = 0; i < teams - 1; i++)

                {

                    SetContest(teams, sideA, sideB);

                    if (teams > 2)

                        ReArrangeSides(teams / 2, ref sideA, ref sideB);

                }

            }

            private void SetContest(int teams, string[] sideA, string[] sideB)

            {

                for (int i = 0; i < (teams / 2); i++)

                {

                    Match contest = new Match();

                    contest.MatchName = sideA[i] + " vs " + sideB[i];

                    contest.TeamA = Convert.ToInt32(sideA[i].Replace("Team", ""));

                    contest.TeamB = Convert.ToInt32(sideB[i].Replace("Team", ""));

                    sch.Add(contest);

                }

            }

            private void ReArrangeSides(int size, ref string[] sideA, ref string[] sideB)

            {

                string temp = sideA[size - 1];

                for (int i = size - 1; i > 1; i--)

                {

                    sideA[i] = sideA[i - 1];

                }

                sideA[1] = sideB[0];

                for (int i = 0; i < size - 1; i++)

                {

                    sideB[i] = sideB[i + 1];

                }

                sideB[size - 1] = temp;

            }

        }

        public class ProKabaddiTournamentWithConstraints : ITournament

        {

            private List<Match> sch;

            public List<Match> BaseTournament

            { get { return sch; } set { sch = value; } }

            public List<Match> PrepareMatches(int nTeams)

            {

                List<Match> sch = this.sch;

                DrawMatchDays(nTeams, ref sch);

                return sch;

            }

            public List<Match> Tournament

            { get { return sch; } }

            private void DrawMatchDays(int nTeams, ref List<Match> matches)

            {

                int[,] match_matrix = DrawDays(nTeams);

                foreach (Match match in matches)

                {

                    int r = match.TeamA;

                    int c = match.TeamB;

                    match.MatchDayHome = match_matrix[r - 1, c - 1];

                    match.MatchDayAway = match_matrix[c - 1, r - 1];

                }

            }

            private int[,] DrawDays(int nTeams)

            {

                int day_limit = nTeams < 7 ? 1 : 2;

                int n_matches = (nTeams * (nTeams - 1)) / 2;

                int[,] matches = new int[nTeams, nTeams];

                int curr_day_matches = 0;

                int m_day = 0;

                int done = 0;

                bool IsBreak = false;

                while (m_day <= n_matches + 10)

                {

                    m_day++;

                    curr_day_matches = 0;

                    IsBreak = false;

                    for (int r = 0; r < nTeams; r++)

                    {

                        for (int c = r + 1; c < nTeams; c++)

                        {

                            if (matches[r, c] == 0)

                            {

                                if (IsAvailable(m_day, r, c, nTeams, ref matches))

                                {

                                    matches[r, c] = m_day;

                                    done++;

                                    curr_day_matches++;

                                    if (curr_day_matches == day_limit)

                                    {

                                        IsBreak = true;

                                        break;

                                    }

                                }

                            }

                        }

                        if (IsBreak)

                            break;

                    }

                    if (done >= n_matches)

                        break;

                }

                for (int r = 0; r < nTeams; r++)

                {

                    for (int c = 0; c < r; c++)

                    {

                        if (r > c)

                        {

                            matches[r, c] = matches[c, r] + m_day + 1;

                        }

                    }

                }

                return matches;

            }

            private bool IsAvailable(int day, int r, int c, int nTeams, ref int[,] matches)

            {

                bool res = true;

                int prev_day = day == 1 ? day : day - 1;

                for (int i = 0; i < nTeams; i++)

                {

                    if (matches[i, c] == day || matches[i, c] == prev_day)

                    {

                        res = false;

                        break;

                    }

                    else if (matches[c, i] == day || matches[c, i] == prev_day)

                    {

                        res = false;

                        break;

                    }

                    else if (matches[r, i] == day || matches[r, i] == prev_day)

                    {

                        res = false;

                        break;

                    }

                    else if (matches[i, r] == day || matches[i, r] == prev_day)

                    {

                        res = false;

                        break;

                    }

                }

                return res;

            }

        }

    }