1. THE CHINESE
POSTMAN PROBLEM
Liz Biz and Hells Bells

2. The Problem Walking the same way again and again
Taking all day to do his round
Time and money
“Money is the route of all evil” Kiara
Dec 04

3. Definitions Nodes: Where edges meet Edge Member of U2! Non-directive
Arc
Directive
Non-directive means you can go in both directions. Directive means you can only go in one direction along the line.

4. Graphs Eulerian Graph: All nodes are even
Start and finish at same place
Semi-Eulerian:
Two odd nodes, the rest are even
Start and finish at different places

5. How to make a graph Eulerian
Count and label the odd nodes
If there is an odd number, this will not work.
List the possible combinations of pairings
Pair up the shortest routes A B C D

6. How to make a graph Eulerian
List the possible combinations for joining the nodes
Odd nodes
Combinations 2
1=1 4
3*1=3 6
5*3*1=15 8
7*5*3*1=105 n
n-1*n-3…*1

7. A B C D 7 5 6 4

8. How to find the total distance
Add up all the edges on the graph
Then add on the length of the extra edges created by the odd vertices

9. A B C D 7 5 6 4 2
=39

10. The End