resource lock

Given an n-ary tree of resources arranged hierarchically. A process needs to lock a resource node in order to use it. But a node cannot be locked if any of its descendant or ancestor is locked. You are supposed to:
-> write the structure of node
-> write codes for
* Islock()- returns true if a given node is locked and false if it is not
* Lock()- locks the given node if possible and updates lock information
* Unlock()- unlocks the node and updates information.
Codes should be :
* Islock –O(1)
* Lock()- O(log n)
* unLock()- O(log n)