For each unique message we keep the next valid timestamp. If a message is early, we simply discard it returning False. Otherwise, we update the next valid timestamp and return True.
Time: 
class Logger:
def __init__(self):
self.next_message_time = {}
def shouldPrintMessage(self, timestamp: int, message: str) -> bool:
next_timestamp = self.next_message_time.get(message, -1)
if timestamp < next_timestamp:
return False
self.next_message_time[message] = timestamp+10
return True
# Your Logger object will be instantiated and called as such:
# obj = Logger()
# param_1 = obj.shouldPrintMessage(timestamp,message)
We can also do the filtering based on elapsed time.
Time:
class Logger:
def __init__(self):
self.message_time = {}
def shouldPrintMessage(self, timestamp: int, message: str) -> bool:
last_time = self.message_time.get(message, float("-inf"))
elapsed_time = timestamp - last_time
if elapsed_time < 10:
return False
self.message_time[message] = timestamp
return True
# Your Logger object will be instantiated and called as such:
# obj = Logger()
# param_1 = obj.shouldPrintMessage(timestamp,message)
To optimize for space, we can periodically cleanup stale messages.
The cleanup trades off time for space. The worst-case for cleanup would be when messages are all new, because the dict will grow in size fast and it will be more prone to trigger a cleanup. However, we would only trigger a cleanup every 10 seconds. So, in this worst-case scenario, a message would be scanned by cleanup at most twice. As a result, the amortized cost of shouldPrintMessges remains
class Logger:
def __init__(self):
self.last_cleanup_time = float("-inf")
self.message_time = {}
def __cleanup_stale_messages(self, timestamp):
if len(self.message_time) < 1000 or (timestamp - self.last_cleanup_time) < 10:
return
for msg in self.message_time:
if timestamp - message_time[msg] >= 10:
del message_time[msg]
self.last_cleanup_time = timestamp
def shouldPrintMessage(self, timestamp: int, message: str) -> bool:
self.__cleanup_stale_messages(timestamp)
last_time = self.message_time.get(message, float("-inf"))
if timestamp - last_time < 10:
return False
self.message_time[message] = timestamp
return True
# Your Logger object will be instantiated and called as such:
# obj = Logger()
# param_1 = obj.shouldPrintMessage(timestamp,message)
unreasonably effective 
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