private void placeAmmo(int count) {
		Random rand = new Random();

		while (count > 0) {
			int pos = rand.nextInt(WIDTH_FIELDS * HEIGHT_FIELDS);
			IField field = fieldsMatrix[pos / WIDTH_FIELDS][pos % WIDTH_FIELDS];

			if (field.getType().equals("building") && !field.hasLife()
					&& !field.hasAmmo()) {
				field.setAmmo(true);
				count--;
			}
		}
	}