Time Based Key-Value Store Solution
Design a time-based key-value data structure that can store multiple values for the same key at different time stamps and retrieve the key's value at a certain timestamp.
Problem statement
Design a time-based key-value data structure that can store multiple values for the same key at different time stamps and retrieve the key's value at a certain timestamp.
Implement the TimeMap class:
TimeMap() Initializes the object of the data structure. void set(String key, String value, int timestamp) Stores the key key with the value value at the given time timestamp. String get(String key, int timestamp) Returns a value such that set was called previously, with timestamp_prev <= timestamp. If there are multiple such values, it returns the value associated with the largest timestamp_prev. If there are no values, it returns "".
First Attempt
It failed with error : Time Limit Exceeded.
Second Attempt
Instead of using List, I can try using TreeMap. A TreeMap is a Red-Black tree-based NavigableMap implementation that stores keys in sorted order.
We use the floorEntry method of the TreeMap to get the closest timestamp lower than or equal to the requested timestamp.
Consider a TreeMap with the following key-value pairs: {1: "a", 3: "b", 5: "c"}. Let's assume you call the floorEntry method with the argument 4. Since 4 is greater than 3 but less than 5, the method will return the entry with the key 3 and value "b".
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