core practice · coding problem
Merge overlapping intervals
Merge [[1,3],[2,6],[8,10],[15,18]] → ?
The mechanism
Interval problems almost always start by sorting — usually by start time, sometimes by end. After sorting, a single pass with a couple of running variables (last end, current count) handles merge, overlap, scheduling, and room allocation.
Expected evidence
[[1,6],[8,10],[15,18]].
Try this drill in the practice workspace →
Hints when you need them
- Sort by start.
- Extend current if overlap.