\begin{Schunk}
\begin{Sinput}
  levels(x)
\end{Sinput}
\begin{Soutput}
[1] "A"    "BorC"
\end{Soutput}
\begin{Sinput}
  levels(x) <- c("A","B")
  table(x)
\end{Sinput}
\begin{Soutput}
x
A B 
1 4 
\end{Soutput}
\end{Schunk}
