Question

Binary Search Trees can be used to implement Maps. Discuss the pros and cons of this in terms of performance. Are there any unique benefits of using a Binary Search Tree to implement a map?

Answer 1

Binary Search Trees use self balancing. Hash tables are used for operations internal maps.

Pros

1) With BST the insert, delete operations are done in O(log n) times whereas in hashing it can be done using O(1) time. (best case) worst case being O(n) with collision of all data. BST's complexity remains same even in worst case so that's an advantage.

2) BSTs are very easy to implement in any language and hashing is a complicated process.

3) BST is cost effective and hashing is costly. Even resizing creates lot of trouble with hashing.

4) BST stores in sorted manner. Hash table doesn't this is an added advantage with BST

Cons

1) Since complexity is O(log n) throughout, hash function optimizations give O(1) complexity most of the times. So BST is slower in comparison

Unique benefit is the sorted order of stored items which is random otherwise