Level 5 · Advanced Problem SolvingBUILD YOUR INTUITION
Intervals
Represent each range by its endpoints and sort by start so overlapping groups can be processed in one sweep.
THE MENTAL MODELWhen should this come to mind?
Represent each range by its endpoints and sort by start so overlapping groups can be processed in one sweep.
Merge overlapsCalendar rangesDisjoint coverage What makes it work
Specify closed versus half-open endpoints. In the published lesson, touching closed intervals overlap.
When to choose something else
Repeated online insertions and overlap queries may require an interval tree or another indexed structure.
See the pattern in action
Change the input. Follow the state. Make it yours.