Example $3\mathrm{.}12.$ A project has fourteen activities A through $M.$ The relationships which obtain amongst these activities are given below.

$($i$)A$ is the first operation.

$($ii$)B$ and $C$ can be performed in parallel and are immediate successor to $A.$

$($iii$)D,E$ and $F$ follow $B.$

$($iv$)G$ follows $E.$

$($v$)H$ follows $D,$ but it cannot start until $E$ is complete.

$($vi$)$ I and $J$ succeed $G.$

$($vii$)F$ and $J$ precede $K.$

$($viii$)H$ and I precede $L.$

$($ix$)M$ succeeds $L$ and $K.$

$($x$)$ The last operation $N$ succeeds $M$ and $C.$

Construct the network diagram.