I’ve been working on this problem for several days but still struggle.↵
↵
The problem involves an N-ary tree (where each non-leaf node has exactly n children). The goal is to implement a Lock() operation with the following rules:↵
↵
Lock(string X, int id):↵
↵
If node X is already locked, you cannot lock it, so return false.↵
If any of X's descendants are locked, you cannot lock it, so return false.↵
If any of X's ancestors are locked, you cannot lock it, so return false.↵
If none of the above conditions are met, lock node X with the given ID and return true.↵
↵
You are required to handle M queries of the Lock() operation on a multi-core machine, allowing M threads to run the Lock() function concurrently. However, since the function involves multiple internal checks, locking two nodes simultaneously can result in race conditions.↵
↵
How would you make the Lock() function thread-safe?
↵
The problem involves an N-ary tree (where each non-leaf node has exactly n children). The goal is to implement a Lock() operation with the following rules:↵
↵
Lock(string X, int id):↵
↵
If node X is already locked, you cannot lock it, so return false.↵
If any of X's descendants are locked, you cannot lock it, so return false.↵
If any of X's ancestors are locked, you cannot lock it, so return false.↵
If none of the above conditions are met, lock node X with the given ID and return true.↵
↵
You are required to handle M queries of the Lock() operation on a multi-core machine, allowing M threads to run the Lock() function concurrently. However, since the function involves multiple internal checks, locking two nodes simultaneously can result in race conditions.↵
↵
How would you make the Lock() function thread-safe?
