Enemy spawn

Hello
I have a question. I´m making a zombie game were come different numbers of zombies in waves. The number of zombies I have in an array. And I have 9 different spawnpoints were they can spawn.
My question is how can I spawn a wave of zombies were each is at a different spawnpoint?

A simple solution would be (as touched upon by ShadoX) to create Lists of points.

Create two lists, one for the original spawn points - and one for the ones that have not been given to any zombie. The code is self explanatory:

	List<Vector3> spawnPoints = new List<Vector3>();
	List<Vector3> tmpSpawnPoints = new List<Vector3>();

	void resetSpawnPoints()
	{
		tmpSpawnPoints.Clear();
		foreach(Vector3 v in spawnPoints)
		{
			tmpSpawnPoints.Add(v);
		}
	}

	Vector3 getRandomPointFromList()
	{
		if(tmpSpawnPoints.Count <= 0)
			resetSpawnPoints();

		int random = Random.Range(0,tmpSpawnPoints.Count);
		Vector3 tmpPosition = tmpSpawnPoints[random];

		tmpSpawnPoints.RemoveAt(random);

		return tmpPosition;
		
	}