With approach $1,$ the simplest approach to eliminating the hold$-$and$-$wait condition, process $p$ must request all resources at the time when the first resource is needed and then release each resource when no longer needed.

The table below shows when each resource is first needed $($start$)$ and when each resource may be released $($end$).$

$\backslash$table$[[,$Start,End$],[r1,3,7],[$r$2,5,10],[$r$3,9,12]]$

For each resource, determine the total time the resource is unavailable $($Total$)$ and the time each resource is unavailable even though process $p$ is not using the resource $($Wasted$).$

$\backslash$table$[[,$Total,Wasted$],[$r$1,,],[$r$2,,],[$r$3,,]]$