Schedule Meeting / Meeting Scheduler (interval scheduling with updates and deletions)

Problem: Schedule Meeting (interval scheduling with updates and deletions) You are given a set of existing meetings (unordered). Each meeting is a half-open interval [start, end) where start < end. Implement a calendar module supporting: schedule(start, end): Try to add a new meeting [start, end). If it overlaps any existing meeting, return false (do not add it). Otherwise, add it and return true. purge(t): Given a fixed time t, delete all meetings whose end time <= t. After deletion, they should not participate in future conflict checks. Task Design and implement the two operations. Discuss what data structure can optimize the runtime (e.g., an ordered map / balanced BST). Constraints Number of operations Q up to 2 * 10^5 0 <= start, end, t <= 10^9 Edge cases to cover Empty calendar insert and purge Touching endpoints: e.g. [10,20) and [20,30) are not overlapping Correct behavior after purging and re-inserting Example I/O format First line: integer Q Next Q lines: S start end for schedule P t for purge Print true/false for each S operation. (See sample testcases in the Chinese section.) Example Input 6 S 10 20 S 15 18 S 20 25 P 20 S 5 10 S 9 12 Output true false true true false