C#

public struct Match 
{
	public int Team1;
	public int Team2;

	public Match(int t1, int t2)
	{
		Team1 = t1;
		Team2 = t2;
	}
}

object dummy = new object();

int teamsCount = 200;
ArrayList matchesList = GetMatches(teamsCount); //create list of matches to be done
Hashtable tokenMatches = new Hashtable();
for (int i = 1; i < teamsCount; i++) 
{
	ArrayList matchesInRound = new ArrayList();
	Hashtable tokenTeams = new Hashtable();
	foreach (Match match in matchesList) 
	{
		if (!tokenMatches.ContainsKey(match) 
			&& !tokenTeams.ContainsKey(match.Team1) 
			&& !tokenTeams.ContainsKey(match.Team2))
		{
			matchesInRound.Add(match);
			tokenMatches.Add(match, dummy);
			tokenTeams.Add(match.Team1, dummy);
			tokenTeams.Add(match.Team2, dummy);
		}
	}

	//Round ready
	Console.WriteLine("Round " + i + ": ");
	foreach (Match match in matchesInRound) 
	{
		Console.WriteLine("   " + match.Team1 + "-" + match.Team2);
	}
}