981. Time Based Key-Value Store

Practice Time Based Key-Value Store for free on NudgeCode: Medium, Binary Search pattern. Write it in Python or JavaScript, run the tests in your browser, and ask for a hint when you are stuck.

Design a key-value store that keeps every version of a value, each tagged with a timestamp.

• set(key, value, timestamp) stores value for key at time timestamp.
• get(key, timestamp) returns the value set for key at the largest timestamp that is <= timestamp, or "" if there is none.

Each test is a list of operations and their arguments; the expected output lists what each call returns (null for the constructor and for calls that return nothing).

Example

["TimeMap","set","get","get","set","get","get"]
[[],["foo","bar",1],["foo",1],["foo",3],["foo","bar2",4],["foo",4],["foo",5]]
->  [null,null,"bar","bar",null,"bar2","bar2"]

Constraints

• Timestamps passed to set are strictly increasing across all calls
• 1 <= key.length, value.length <= 100
• 1 <= timestamp <= 10^7
• Up to 2 * 10^5 calls in total