Here is an algorithm for calling a friend on the telephone: Step Operation $1.$ Dial the phone and wait for either an answer or a busy signal $2.$ If the line is not busy then do Steps $3$ and $43.$ Talk as long as you want $4.$ Hang up the phone, you are done $5.$ Otherwise $($the line is busy$)6.$ Wait exactly $1$ minute $7.$ Go back to Step $1$ and try again During execution, this algorithm could get into a situation in which, as in the deadlock problem, no useful work can ever get done. Describe the problem, explain why it occurs, and suggest how it could be solved