function that updates the entry of the tree only if it exists

[abdullahemad12]

Task

This should be like the normal update function, however it does not insert a new entry if no entry was found. You should also write tests for this function as well

Interface

/**
  * cranbtree_t*, int, void* -> void
  * MODIFIES: cranbtree_t* 
  * EFFECTS: Updates the object of the entry that has the specified key with the new pointer only if it 
  * exists. 
  * PARAMETERS: 
  * - cranbtree_t* cbt, pointer to the BTree struct
  * - int key: the key of the entry to be updated
  * - void* object: pointer to the object
  * RETURNS: pointer to the old object, or NULL if it does not exist
  */
void* cbt_update_if_exists(cranbtree_t* bt, int key, void* object);

Where to code

You will find a stub for the function in src/cranbtree.c. You should complete this function

hint:

think how this function is different from the original update and how you could reuse existing code