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$ curl repovive.com/roadmaps/graph-theory/euler-tour-technique

░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░██████████████████████████████████████████████████████████████

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$ curl repovive.com/roadmaps/graph-theory/euler-tour-technique

Lessons

1. Intro

2. What is an Euler Tour

3. Entry and Exit Times

Practice Problems

Ready to start learning?

4. Subtrees as Ranges

5. Flattening the Tree

6. Basic Implementation

7. Example Tree

8. Check Your Understanding

9. Problem - Subtree Queries

10. Key Idea - Subtree to Range

11. Key Idea - Which Times to Use

12. Algorithm

13. Subtree Queries - Implementation

14. Subtree Queries - Walkthrough

15. Lessons Learned

16. Euler Tour Variants

17. Entry-Only Variant

18. Entry-Exit Variant

19. Full Tour Variant

20. Check Your Understanding

21. Problem - Path Queries

22. Key Idea - Path as Prefix

23. Key Idea - Prefix Sum Trick

24. Algorithm

25. Path Queries - Implementation

26. Path Queries - Walkthrough

27. Lessons Learned

28. Combining with Segment Trees

29. BIT as Lighter Alternative

30. Space Complexity

31. Update Types

32. Query Types

33. Ancestor Check

34. Rerooting Limitation

35. Check Your Understanding

36. DFS Order Matters

37. Connection to Heavy-Light Decomposition

38. Practical Tips

39. Common Mistakes

40. Problem - Company Queries II

41. Key Idea - LCA via Euler Tour

42. Algorithm

43. Company Queries II - Implement Solution

44. Lessons Learned

45. Section 13 Recap