private HashMap<Item,Integer> resourcesPerPlayer(ActivePlayer player)
	{		
		HashMap<Item,Integer> contributions = new HashMap<Item,Integer>();
		
		Set<Item> resources = resourcesNeeded.keySet();
		for (Item resource : resources)
		{
			Skill neededSkill = skillResources.get(resource);
			if (player.getSkill() != neededSkill) continue;

			int amountNeeded = resourcesNeeded.get(resource);
			int amountFound = player.inventory.containsNum(resource);			
			if (amountFound > 0)
				contributions.put(resource, Math.min(amountNeeded, amountFound));
		}
		
		if (contributions.size() > 0)
			return contributions;
		else
			return null;
	}