SOLUTION

A process can enter into its critical section when it receives a reply message from all other processes in the system.

Mutual exclusion is ensured by this algorithm. If two processes entered their critical sections at the same time, it would mean that each process sent a request, received the other process’s request, compared the time stamps, and found that the other process’s request had a lower timestamp than its own. This is not possible; therefore, mutual exclusion is ensured.