@Override
	public void undo(Board board) {
		if (this.out != Counter.EMPTY) {
			board = this.moveUpCells(board, this.getCol()); // if the column is full I move the counters one up to put the first counter out of the "printed board" in and make disappear the first counter
			board.setPosition(getCol(), board.getHeight(), this.getOut());
		}
		else {
			int h = Util.firstEmptyPosition(board, this.getCol());
			if (h < Util.ERRORTHRESHOLD) {
				h++;
			}
			board.setPosition(this.getCol(), (h + 1), Counter.EMPTY); // the same undo as C4
		}
	}