Problem 16
Description
This problem was asked by Twitter.
You run an e-commerce website and want to record the last N
order
ids in a log. Implement a data structure to accomplish this, with the following API:
record(order_id)
: adds the order_id to the logget_last(i)
: gets the ith last element from the log. i is guaranteed to be smaller than or equal to N.
You should be as efficient with time and space as possible.