LeetCode 981, Medium. Topics: Hash Table, String, Binary Search, Design. View on LeetCode.
Generate this problem as a practice environment: tested reference solution, 12 parametrized pytest cases, and a playground notebook:
Problem
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 "".
Examples
Explanation:
Constraints
1 <= key.length, value.length <= 100
key and value consist of lowercase English letters and digits.
1 <= timestamp <= 10^7
- All the timestamps
timestamp of set are strictly increasing.
- At most
2 * 10^5 calls will be made to set and get.
Solution
Reference implementation from solution.py on GitHub, full suite in test_solution.py:
Complexity
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