time-based-key-val

Time Based Key-Value Store

With dictionary:

class TimeMap(defaultdict):
    def __init__(self):
        super().__init__(dict)
 
    def set(self, key: str, value: str, timestamp: int) -> None:
        self[key][timestamp] = value
 
    def get(self, key: str, timestamp: int) -> str:
        max_time = 0
        res = ""
        for time, val in super().get(key, {}).items():
            if max_time < time <= timestamp:
                max_time = time
                res = val
        return res

With binary search

class TimeMap(defaultdict):
    def __init__(self):
        super().__init__(list)
 
    def set(self, key: str, value: str, timestamp: int) -> None:
        self[key].append((timestamp, value))
 
    def get(self, key: str, timestamp: int) -> str:
        index = bisect_right(super().get(key, []), timestamp, key=lambda x: x[0])
        return self[key][index - 1][1] if index else ""

Notice the usage of bisect_right.