Is Design Event Manager easy or hard?

Design Event Manager is generally considered a medium difficulty problem. The logic is straightforward once you recognize the need for an ordered structure, but choosing the correct data structure and handling operations efficiently requires solid data structure knowledge.

Design Event Manager Python/Java solution

Python solutions often simulate a sorted set using bisect with a sorted list or third‑party ordered set libraries. Java uses TreeSet directly, while C++ uses std::set. Each provides O(log n) insertion, deletion, and neighbor lookup operations.

How to solve Design Event Manager in O(log n)?

Store all events inside a sorted structure such as a TreeSet, ordered set, or balanced BST. Each new event is inserted while maintaining order. Queries like finding the next event use ceiling or lower_bound operations, which run in O(log n).

What is the best approach for Design Event Manager?

The most efficient approach uses a Sorted Set or balanced binary search tree. This structure keeps events automatically ordered while supporting insertion, deletion, and lookup in O(log n) time. It allows quick retrieval of the earliest event or the next event after a given timestamp.

Is Design Event Manager asked at Google/Amazon/Meta?

Design-style data structure problems similar to this appear frequently in interviews at large companies such as Google, Amazon, and Meta. They test your ability to choose appropriate data structures for efficient insert, delete, and query operations.

What data structure is used in Design Event Manager?

A Sorted Set or balanced binary search tree is typically used. Examples include TreeSet in Java, std::set in C++, or ordered set implementations in Python and Go. These structures maintain elements in sorted order and support logarithmic operations.

What is the time complexity of Design Event Manager?

Using a Sorted Set implementation, inserting, deleting, or searching for an event takes O(log n) time. The space complexity is O(n) because all scheduled events must be stored. A naive list-based approach may require O(n) time per query.

3885. Design Event Manager - Practice Online

You are given an initial list of events, where each event has a unique eventId and a priority.

Implement the EventManager class:

EventManager(int[][] events) Initializes the manager with the given events, where events[i] = [eventId_i, priority_i].
void updatePriority(int eventId, int newPriority) Updates the priority of the active event with id eventId to newPriority.
int pollHighest() Removes and returns the eventId of the active event with the highest priority. If multiple active events have the same priority, return the smallest eventId among them. If there are no active events, return -1.

An event is called active if it has not been removed by pollHighest().

Example 1:

Input:
["EventManager", "pollHighest", "updatePriority", "pollHighest", "pollHighest"]
[[[[5, 7], [2, 7], [9, 4]]], [], [9, 7], [], []]

Output:
[null, 2, null, 5, 9]

Explanation

EventManager eventManager = new EventManager([[5,7], [2,7], [9,4]]); // Initializes the manager with three events
eventManager.pollHighest(); // both events 5 and 2 have priority 7, so return the smaller id 2
eventManager.updatePriority(9, 7); // event 9 now has priority 7
eventManager.pollHighest(); // remaining highest priority events are 5 and 9, return 5
eventManager.pollHighest(); // return 9

Example 2:

Input:
["EventManager", "pollHighest", "pollHighest", "pollHighest"]
[[[[4, 1], [7, 2]]], [], [], []]

Output:
[null, 7, 4, -1]

Explanation

EventManager eventManager = new EventManager([[4,1], [7,2]]); // Initializes the manager with two events
eventManager.pollHighest(); // return 7
eventManager.pollHighest(); // return 4
eventManager.pollHighest(); // no events remain, return -1

Constraints:

1 <= events.length <= 10⁵
events[i] = [eventId, priority]
1 <= eventId <= 10⁹
1 <= priority <= 10⁹
All the values of eventId in events are unique.
1 <= newPriority <= 10⁹
For every call to updatePriority, eventId refers to an active event.
At most 10⁵ calls in total will be made to updatePriority and pollHighest.