algorithm - Search, Insert, Delete and DeleteLast operations in logN -


what can best suited data structure supports following operations in o(log n) time: 

search(x) finds element key x  insert(x) insert element key x     delete(x) delete element key x     deletelast() removes inserted element

i know binary search tree can handle first 3 operations pretty good. how handle fourth query. if bst not solution tell can best suited data structure handling 4 queries.

credit @thomasjungblut bringing solution up.

first, build bst hold information need in leaves of tree.
in self solves search, insert & delete requirements.
address "delete inserted element" requirement add structure of each leaf prev & next fields, this:

struct leaf {     int key;     info_struct info; }

becomes this:

struct leaf {     int key;     info_struct info;     leaf *prev;     leaf *next; }

and except holding root of bst, hold leaf *last. every time new element added, point 1 before , last updated.

note: addition helps finding requested item, deletion takes log(n).

edited @alexeishestakov


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