\item \self Construct a ROBDD for the formula

$$f =(a\land d\land c)\lor(b\land\lnot d\land\lnot a)\lor(c \implies \lnot d) \lor (a \implies \lnot b)$$

using \textit{variable order} $b < a < d < c$. Use complemented edges and a node for \texttt{true} as the only constant node. To simplify drawing, you may assume that \textit{dangling edges} point to the constant node. Write down all cofactors that you compute to obtain the final result and mark them in the graph.
