Is there any leetcode problem using this technique?
I ended up getting a line sweep problem in a codesignal question.
https://leetcode.com/problems/maximum-population-year/discuss/1198846/sweep-line-algorithm-with-explanation
As a reference, here are few more problems that could be solved by sweep line:
https://leetcode.com/problems/my-calendar-iii/submissions/
https://leetcode.com/problems/employee-free-time/submissions/
https://leetcode.com/problems/meeting-scheduler/submissions/
This series of questions can be well-answered by the line sweep algorithm.