$9\mathrm{.}12.$ For the art gallery layout shown in Fig. P$9\mathrm{.}12,$ an attendant placed at a doorway can supervise the two adjacent rooms. Determine the smallest number of attendants for supervising all the rooms. IGURE P$8\mathrm{.}2$ Figure P$9\mathrm{.}12($Hint: If x$\_$j is $0-1$ variable representing attendant placed at door j$,$ for any room sum of attendants must be equal to $1.$ For top left room x$\_1+$x$\_2>=1.$ Minimize the sum of all x$\_$j$.$ Solve using program ZeroOne$)$