# A (Unique) Exchange Game on Bispanning Graphs

With this Java Applet you can play the (unique) exchange game on a bispanning graph, which was the topic of my diploma thesis. You can also launch the applet with Java WebStart: , which will appear as a larger window outside the browser. The source code of the Java Applet is available on github or in a local zip archive. If you do not have Java installed, please refer to these instruction.

## Instructions

In the game, you play Alice's role and want to **flip all edge colors** of the graph. Bob will try to prevent you from doing this. Bob is played by the computer. Try to achieve it in the **minimum number of moves necessary**. Once you found solutions to simple random graphs, try the **"difficult"** ones from the "named graph" menu.

If you want to make it easier to reach the minimum number of moves, try to restrict yourself to **unique exchanges**, which leave Bob no choice. To show unique exchanges as thicker edges, press right click and select "restrict to unique exchanges" in the options context menu.

Some tips on the Applet's user interface:

- Clicking edges in the graph will flip their color. The original color stays visible as the smaller line stroke inset in the edges.
- You can move vertices around by dragging them with the left mouse button.
- Right-click and drag the board to move the whole graph.
- The mouse wheel zooms the graph in and out. Ctrl+mouse wheel changes the edge line width.
- Right-click the board to show a full context menu of operations. (Writing and read files only works with the Java WebStart version).
- To add vertices or edges, hold the Ctrl key, and click to create a vertex or click-and-drag to create an edge.
- You can draw a custom graph by starting with the empty graph (a random graph with zero vertices), and then add vertices and edges by holding the Ctrl key.