1. FLIPPED CLASSROOM ACTIVITY CONSTRUCTOR – USING EXISTING CONTENT

2. Table of Contents SLIDE # SECTION 13 18 24 ABOUT YOU 4
OUT-OF-CLASS SEGMENT 13
IN-CLASS SEGMENT 18
EVALUATION 24

3. About me
Myself Dr.Nagalakshmi Venugopal working as Associate Professor in Computer Science & Engineering , Dr.N.G.P Institute of technology , coimbatore. Topic : Red Black Trees

4. Dr.Nagalakshmi venugopal
RED BLACK TREES
DATA STRUCTURES
COMPUTER SCIENCE
II yr CSE Students
ANNA UNIVRSITY,CHENNAI

5. Red Black Trees

6. About Out-of-Class Segment
The concept of Red Black Tree in real time used in process scheduler in Linux Operating system.
Its basic of Binary Search Tree.
It comes under Recall and understand level since it is an basic concept in data structures.
In this presentation I have provided some slides, video links and some explanation about the concept of red black trees.

7. Out-of-class Activity Design -1
Learning Objective(s) of Out-of-Class Activity
At the end of watching the videos student should be able to
Construct Red Black trees (Apply Level)
Explain the Red black trees and its operation(Understand Level)
Can able to Insert ,Delete element in Red Black Trees(Apply Level)
Key Concept(s) to be covered
Red Black Trees.
Construct , Insertion and Deletion of element .

8. Red Black Trees
Red-black trees are a variation of binary search trees to ensure that the tree is balanced.
Height is O(lg n), where n is the number of nodes.
Operations take O(lg n) time in the worst case.

9. Red Black trees key, left, right, and p.
Binary search tree + 1 bit per node: the attribute color, which is either red or black.
All other attributes of BSTs are inherited:
key, left, right, and p.
All empty trees (leaves) are colored black.
We use a single sentinel, nil, for all the leaves of red-black tree T, with color[nil] = black.
The root’s parent is also nil[T ].

10. Red-black Tree – Example26
Remember: every internal node has two children, even though nil leaves are not usually shown. 17 41
nil[T] 30 47 38 50

11. Properties Every node is either red or black. The root is black.
Every leaf (nil) is black.
If a node is red, then both its children are black.
For each node, all paths from the node to descendant leaves contain the same number of black nodes.

12. Insertion Insertion must preserve all red-black properties.
Should an inserted node be colored Red? Black?
Basic steps:
Use Tree-Insert from BST (slightly modified) to insert a node x into T.
Procedure RB-Insert(x).
Color the node x red.
Fix the modified tree by re-coloring nodes and performing rotation to preserve RB tree property.
Procedure RB-Insert-Fixup.

13. Deletion
Deletion, like insertion, should preserve all the RB properties.
The properties that may be violated depends on the color of the deleted node.
Red – ?
Black?
Steps:
Do regular BST deletion.
Fix any violations of RB properties that may result.

14. Guidelines for Video Selection - 2
Main Video Source URL
License of Video
NPTEL Youtube Channel

15. Out-of-class Activity Design - 2
Main Video Source URL
License of Video
CC-BY-SA (reuse allowed)
Mapping Concept to Video Source
CONCEPT
VIDEO SEGMENT
DURATION
(in min)
RED BLACK TREES V1
13.25
INSERTION
V2https://youtu.be/0lWsHUiAcOc
10.22
DELETION V3
12.30
TOTAL DURATION
36.15 min

16. Out-of-class Activity Design - 3
Aligning Assessment with Learning Objective
Learning Objective
Assessment Strategy
Expected Duration
(in min)
Additional Instructions (if any)
Red Black Tree: Construction
Q. Construct a Red black tree for the following nodes
10 minutes
Watch V1 and then answer Q1

17. Out-of-class Activity Design - 3
Aligning Assessment with Learning Objective
Learning Objective
Assessment Strategy
Expected Duration
(in min)
Additional Instructions (if any)
Insert a node in Red Black Tree
Q1. Create a Red black tree with nodes
Q2. Insert nodes to the above created Red black Tree
10 minutes
Watch V1 and V2 and then answer Q1 and Q2

18. Out-of-class Activity Design - 3
Aligning Assessment with Learning Objective
Learning Objective
Assessment Strategy
Expected Duration
(in min)
Additional Instructions (if any)
Deleting a node from Red Black Tree
Q1. Create a Red black tree with the nodes
Q2. Delete node 9 8 from the tree.
10 minutes
Watch Video V1 and V3 to answer the
Question 1 and 2.
Total activity duration
30 minutes

19. In-class Activity Design -1
Learning Objective(s) of In - Class Activity
At the end of the class, students will be able to,
Construct Red Black Tree .
Key Concept(s) to be covered
Red Black Tree : Construction, Insertion and Deletion.

20. In-class Activity Design -1
Learning Objective(s) of In-Class Activity
At the end of the class, students will be able to,
Create a Red Black Tree for any type of problems (ANALYZE Level)
Implement Red Black Tree using C/C++
(ANALYZE Level)
Key Concept(s) to be covered
Application of Red Black Tree in Real World Problem Solving.
Implementation using Programming language.

21. In-class Activity Design -2
Active Learning activity(ies) that you plan to do
Think - pair - share
Explain the strategy by giving details of
Teacher poses a problem and ask the students to think a while, then ask the student to construct a red black tree.
The students will construct the given red black tree and discuss among them and then share the ideas.
Justify why the above is an active learning strategy
Learning happens in think phase, pair phase and share phase.

22. In-class Activity Design -2
Active Learning activity(ies) that you plan to do
Real world problem solving using.
Think-Pair-Share
Concept clarification using.
Peer Instruction

23. In-class Activity Design -2
Peer Instruction Strategy
Q 1: What is the special property of red-black trees and what root should always be? a) a color which is either red or black and root should always be black color only b) height of the tree c) pointer to next node d) a color which is either green or black 

24. In-class Activity Design -2
Peer Instruction Strategy –
 Q 2: Which of the following is an application of Red-black trees and why?
a) used to store strings efficiently b) used to store integers efficiently c) can be used in process schedulers, maps, sets d) for efficient sorting

25. In-class Activity Design -2
Peer Instruction Strategy –
 Q 3: What are the operations that could be performed in O(logn) time complexity by red-black tree?
a) insertion, deletion, finding predecessor, successor b) only insertion c) only finding predecessor, successor d) for sorting

26. In-class Activity Design -2
Peer Instruction Strategy –
For each question they will first vote individually.
Then they will discuss with peers and come to consensus.
Listen to instructors explanation.

27. In-class Activity Design -2
TPS Strategy – What Instructor does
Summarize about the concept of Red Black Tree and its applications.
Ask the students about the answers
Discuss about the answers
Consolidate the final answer and explain it clearly to the students

28. In-class Activity Design -2
TPS Strategy –
--Create a Completely Fair Scheduler  (CFS) is the name of a process scheduler which is used in Linux kernel implement the concept of red black tree.
--It handles CPU resource allocation for executing processes, and aims to maximize overall CPU utilization while also maximizing interactive performance.
--The red black trees are a replacement for run queues which had priorities for processes on the queue for the scheduler to pick up from. 

29. In-class Activity Design -2
TPS Strategy – What Instructor does
Think (~2 minutes)
Instruction:
Recall the concept of Red Black Tree
Understand the given problem
Think individually and write the results

30. In-class Activity Design -2
TPS Strategy – What Instructor does
Pair (~5 minutes)
Instruction: Now pair up and compare your answers. Agree on one final answer.
While students are pairing and discussing, instructor goes to 2~3 sections to see
what they are doing.
Now assuming that 6 process are used to construct the scheduler .

31. In-class Activity Design -2
TPS Strategy – What Instructor does
Share (~8 minutes)
Instructor asks a group to share their answer with class and see whether there are different answers. After sharing is done, instructor gives feedback on the correct solution and how to construct the Scheduler using Red Black tree.
In the next iteration of TPS, in the Think Phase we ask students to convert the Insertion and deletion of process in scheduler.
In the pair phase we ask students to compare the answers.
In the share phase again the different answers are sought.

32. In-class Activity Design -2
TPS Strategy – What Instructor does
Pair (~5 minutes)
Instruction: Students are pair up and compared with their answers .

33. In-class Activity Design -2
Justify why the above is an active learning strategy
In both the above strategies, students are required to go beyond mere listening and execution of prescribed steps. They are required to think deeply about the content they were familiarized in out-of-class and do higher order thinking.
There is also feedback provided (either through peer discussion or instructor summary)

34. In-class Activity Design -2
TPS Strategy – What Instructor does
Share (~8 minutes)
Each group share their answer and instructor gives feedback on the correct solution.

35. In-class Activity Design -2
In both the above strategies, students are required to go beyond mere listening and execution of prescribed steps. They are required to think deeply about the content they were familiarized in out-of-class and do higher order thinking.