leetcode1348

 1 import bisect
 2 class TweetCounts:
 3     def __init__(self):
 4         self.records = {}
 5 
 6     def recordTweet(self, tweetName: str, time: int) -> None:
 7         if tweetName not in self.records:
 8             self.records[tweetName] =  [time]
 9         else:
10             bisect.insort(self.records[tweetName],time)
11             # self.records[tweetName].append(time)
12 
13     def getTweetCountsPerFrequency(self, freq: str, tweetName: str, startTime: int, endTime: int) -> 'List[int]':
14         result = []
15         # self.records[tweetName].sort()
16         if tweetName not in self.records:
17             return []
18         else:
19             delta = 0
20             if freq == 'minute':
21                 delta = 60
22             elif freq == 'hour':
23                 delta = 60 * 60
24             else:
25                 delta = 60 * 60 * 24
26             i = 0
27             I = (endTime - startTime) // delta + 1
28             while i < I:
29                 start = startTime + delta * i
30                 end = min(startTime + delta * (i + 1),endTime + 1)
31                 left = bisect.bisect_left(self.records[tweetName], start)
32                 right = bisect.bisect_left(self.records[tweetName], end)
33                 count = right - left
34                 result.append(count)
35                 i += 1
36         return result

算法思路：二分查找。

在插入数据的时候，使用插入排序。

在计算区间内符合条件的数值个数的时候，使用两次二分查找。

posted on 2020-02-09 14:27 Sempron2800+ 阅读(184) 评论(0) 编辑收藏举报