Graphs and Euler'sCircuit
Presentation with Sub-topic and Video | Due Next Week
2.
Instructions Overview
• 1.Topic: Graphs and Euler's Circuit
• 2. Research beyond the blackboard
• 3. Choose your own sub-topic related to the
main topic
• 4. Prepare a video related to the topic
• 5. Present next week
3.
Chosen Sub-topic: EulerPaths vs Euler Circuits
• Euler Path: A path that uses every edge of a graph exactly once.
• Euler Circuit: A circuit that uses every edge of
a graph exactly once and starts and ends at
the same vertex.
• We'll compare these two and explore when
each exists.
4.
Examples and Explanation
•Example of Euler Path:
• - A graph with exactly two vertices of odd
degree.
• Example of Euler Circuit:
• - A graph where all vertices have even
degrees.
• We'll use visual aids and simple graphs to
show these.
Sample Graph
5.
Video Resource
• Watchthis video to understand Euler Circuits and Paths in depth:
• https://www.youtube.com/watch?v=GqX3r-
DUdlY
Sample Graph
6.
Reminder
• Make sureto:
• - Understand the topic and sub-topic clearly
• - Watch the video linked in the previous slide
• - Prepare your part and be ready to present
next week!
7.
What is aGraph?
• A graph is a set of vertices (nodes) connected by edges (lines). Graphs can
represent networks like roads, social connections, or circuits.
Degree of aVertex
• The degree of a vertex is the number of edges connected to it. Vertices with even
or odd degrees determine the existence of Euler paths and circuits.
Sample Graph
10.
Conditions for EulerPath
• An Euler Path exists in a graph if there are exactly two vertices with odd degrees.
Sample Graph
11.
Conditions for EulerCircuit
• An Euler Circuit exists if all vertices have even degrees.
Sample Graph
12.
Real-Life Example: Bridgesof Königsberg
• Euler studied the problem of walking through all seven bridges of Königsberg
without repeating a bridge. He proved it was impossible, founding graph theory.
Hamiltonian vs Eulerian
•Eulerian Path uses every edge once.
• Hamiltonian Path visits every vertex once.
20.
Directed Graphs andEuler Circuits
• In directed graphs, Euler circuits exist if the in-degree equals out-degree for all
vertices.
21.
Why Learn EulerCircuits?
• Euler circuits are used in planning, optimization, and solving routing problems like
snow plow routes and garbage collection.
22.
Quiz: Identify theType
• Given a graph with vertex degrees: A(2), B(2), C(2), D(2) — Does it have an Euler
Circuit or Path?
• Answer: Euler Circuit.
23.
Practice Problem
• Drawa graph with 4 vertices that has an Euler Path but not an Euler Circuit.
24.
Review and Recap
•We've covered: Graph basics, Euler paths vs circuits, examples, conditions, real-life
applications, and practice questions.