Interval Problems

4. Merge Intervals - The Idea

Sort by start

5. Merge Intervals - Algorithm

Step by step

6. Merge Intervals - Walkthrough

Tracing the algorithm

7. Merge Intervals - Implementation

The code

8. Quiz: Merge Intervals

Test your understanding

9. Problem - Insert Interval

Add without overlap

10. Insert Interval - Algorithm

Three phases

11. Insert Interval - Implementation

The code

12. Lessons from Merge and Insert

Key patterns

13. Problem - Interval List Intersections

Two sorted lists

14. Interval Intersections - Algorithm

Two-pointer approach

15. Interval Intersections - Implementation

The code

16. Quiz: Interval Intersections

Apply the algorithm

17. Problem - Remove Covered Intervals

Eliminate redundancy

18. Remove Covered - Algorithm

Sort and track

19. Remove Covered - Implementation

The code

20. Problem - Minimum Intervals to Cover

Cover a range

21. Minimum Cover - Algorithm

Greedy extension

22. Minimum Cover - Implementation

The code

23. Quiz: Interval Covering

Apply the pattern

24. Why Sort by End Time?

The selection key

25. Quiz: Sort Order Choice

When to use which

26. Problem - Non-overlapping Intervals

Minimum removals

27. Non-overlapping - The Idea

Maximize to minimize

28. Non-overlapping - Implementation

The code

29. Problem - Meeting Rooms

Can attend all?

30. Meeting Rooms - Algorithm

Overlap detection

31. Meeting Rooms - Implementation

The code

32. Problem - Meeting Rooms II

Minimum rooms needed

33. Meeting Rooms II - Event Sweep

Start and end events

34. Meeting Rooms II - Implementation

The code

35. Quiz: Meeting Rooms

Event sweep understanding

36. The Sweep Line Pattern

Processing events

37. Problem - My Calendar I

Online interval insertion

38. My Calendar I - Algorithm

Linear vs balanced

39. My Calendar I - Implementation

The code

40. Interval Overlap Check

The formula

41. Quiz: Interval Overlap

Testing the formula