A program to find a short path between points (ending at the first point) on a flat euclidean plane using nearest insertion.
Written in Java. "salesman.java" is the source code. "salesman.jar" is a compiled and runnable version of salesman.java.
The way it works is that it starts with any 3 points, then takes a 4th point, finds how it can add it in while increasing the travel time by the least, and inserts it into the list. Rinse and repeat with 4 points, then 5, etc...
This algorithm works well because the place of insertion of lowest increase in a cluster of points will always join the cluster of points together. For instance, it successfully joins together the Alaskan cities in the below example.
Copy-paste the contents of uscities.txt exactly into the program and it will find a short path between the cities. NOTE: The uscities.txt file uses Unix-style line breaks. Copy-pasting into a Windows CMD or PowerShell does not work but copy-pasting into a Linux/Mac Terminal does work and also Cygwin on Windows works.
The data comes from https://gist.github.com/ecarter/413343
To find which number corresponds to which city:
- Add 3
- Look at that line number in https://gist.github.com/ecarter/413343
Because the Earth is not a flat plane the total distance is not accurate but it should still find at least close to the shortest path possible.