Time Based Key-Value Store

Explore how to implement a time-based key-value store that supports storing multiple values for the same key at various timestamps. Understand how to retrieve keys efficiently at specific times by returning the most recent value before the requested timestamp, and learn to design this using custom data structures for scalable solutions.

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Statement

Implement a data structure that can store multiple values of the same key at different timestamps and retrieve the key’s value at a certain timestamp.

You’ll need to implement the TimeStamp class. This class has the following functions:

Init(): This function initializes the values dictionary and timestamp dictionary.
Set Value(key, value, timestamp): This function stores the key and value at any given timestamp.
Get Value(key, timestamp): This function returns the value set for this key at the specified timestamp.

Note: When a query requests the value of a key at a timestamp that isn’t recorded, return the value corresponding to the most recent timestamp before the query’s timestamp. If there are no timestamps before the query’s timestamp, return an empty string.

Constraints:

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