(1) in the use of the tag and return variables, the mutual exclusion condition is guaranteed, and if the two processes are set to true, then there is only one process that will succeed, that is, the turn of the process. When another process updates its return value, the process waits for the process to enter its critical region

(2) the ready process, by mark, return variables, this algorithm does not provide strict alternation, if a process wants to enter its critical section, it can be identified as true, and then enter the critical area of them, when it exits the critical region, it can turn to other processes to set the value of the and, if the process wants to enter the critical region again it in other process bef