635

Author: idf

635 Design Log Storage System.py

@@ -0,0 +1,76 @@
+#!/usr/bin/python3
+"""
+You are given several logs that each log contains a unique id and timestamp.
+Timestamp is a string that has the following format:
+Year:Month:Day:Hour:Minute:Second, for example, 2017:01:01:23:59:59. All domains
+are zero-padded decimal numbers.
+
+Design a log storage system to implement the following functions:
+
+void Put(int id, string timestamp): Given a log's unique id and timestamp, store
+the log in your storage system.
+
+
+int[] Retrieve(String start, String end, String granularity): Return the id of
+logs whose timestamps are within the range from start to end. Start and end all
+have the same format as timestamp. However, granularity means the time level for
+consideration. For example, start = "2017:01:01:23:59:59", end =
+"2017:01:02:23:59:59", granularity = "Day", it means that we need to find the
+logs within the range from Jan. 1st 2017 to Jan. 2nd 2017.
+
+Example 1:
+put(1, "2017:01:01:23:59:59");
+put(2, "2017:01:01:22:59:59");
+put(3, "2016:01:01:00:00:00");
+retrieve("2016:01:01:01:01:01","2017:01:01:23:00:00","Year"); // return [1,2,3],
+because you need to return all logs within 2016 and 2017.
+retrieve("2016:01:01:01:01:01","2017:01:01:23:00:00","Hour"); // return [1,2],
+because you need to return all logs start from 2016:01:01:01 to 2017:01:01:23,
+where log 3 is left outside the range.
+
+Note:
+There will be at most 300 operations of Put or Retrieve.
+Year ranges from [2000,2017]. Hour ranges from [00,23].
+Output for Retrieve has no order required.
+"""
+import bisect
+
+
+class LogSystem:
+    def __init__(self):
+        """
+        BST - TreeMap (java)
+        binary search using time stamp
+        """
+        self.lst = []
+
+    def put(self, id: int, timestamp: str) -> None:
+        bisect.insort(self.lst, (timestamp, id))
+
+    def retrieve(self, s: str, e: str, gra: str) -> List[int]:
+        """
+        Use timestamp comparison
+        Can convert the timestamp to number.
+        """
+        lo = "0001:01:01:00:00:00"
+        hi = "9999:12:31:23:59:59"
+        pre = {
+            "Year": 4,
+            "Month": 7,
+            "Day": 10,
+            "Hour": 13,
+            "Minute": 16,
+            "Second": 19,
+        }[gra]
+
+        s = s[:pre] + lo[pre:]
+        e = e[:pre] + hi[pre:]
+        i = bisect.bisect_left(self.lst, (s, 0))
+        j = bisect.bisect_right(self.lst, (e, float("inf")))
+        return [id for _, id in self.lst[i:j]]
+
+
+# Your LogSystem object will be instantiated and called as such:
+# obj = LogSystem()
+# obj.put(id,timestamp)
+# param_2 = obj.retrieve(s,e,gra)