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花花酱 LeetCode 732. My Calendar III



Implement a MyCalendarThree class to store your events. A new event can always be added.

Your class will have one method, book(int start, int end). Formally, this represents a booking on the half open interval [start, end), the range of real numbers x such that start <= x < end.

K-booking happens when K events have some non-empty intersection (ie., there is some time that is common to all K events.)

For each call to the method, return an integer K representing the largest integer such that there exists a K-booking in the calendar.

Your class will be called like this: MyCalendarThree cal = new MyCalendarThree();, end)

Example 1:

MyCalendarThree();, 20); // returns 1, 60); // returns 1, 40); // returns 2, 15); // returns 3, 10); // returns 3, 55); // returns 3
The first two events can be booked and are disjoint, so the maximum K-booking is a 1-booking.
The third event [10, 40) intersects the first event, and the maximum K-booking is a 2-booking.
The remaining events cause the maximum K-booking to be only a 3-booking.
Note that the last event locally causes a 2-booking, but the answer is still 3 because
eg. [10, 20), [10, 40), and [5, 15) are still triple booked.


  • The number of calls to per test case will be at most 400.
  • In calls to, end)start and end are integers in the range [0, 10^9].


Similar to LeetCode 731 My Calendar II Use an ordered / tree map to track the number of event at current time.

For a new book event, increase the number of events at start, decrease the number of events at end.

Scan the timeline to find the maximum number of events.


Solution 1: Count Boundaries

Time complexity: O(n^2)

Space complexity: O(n)


Solution 2


Solution 3: Segment Tree



Related Problems:

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