Code RoomMinimum class cancellations
MediumPrep Room Coding #662

Minimum class cancellations

CodingAlgorithms & data structuresEntry–Mid~15 min

A yoga studio received proposed class slots for its single room as [start, end] pairs — each occupying the half-open span [start, end), unsorted, possibly overlapping. The studio will cancel some proposals so that the surviving classes never overlap (back-to-back is fine). Return the minimum number of proposals it must cancel. Example: [[9,11],[10,12],[11,13]] requires 1 cancellation.

Implement
min_cancellations(proposals: list[list[int]]) → int
Examples
in[[[9,11],[10,12],[11,13]]]out1
What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

0:00 of about 15 min
InputExpectedGot
[[[9,11],[10,12],[11,13]]]1not run yetsample