Did you ever need to figure out the shortest possible route between A and Z via B, C, D… ?
If so, you have faced the “traveling salesman” problem and touched the field of theoretical computer science.
The TOS is a optimization problem that is really hard to solve – in fact NP-hard.
This Kohonen Neuronal Network aproximates or ‘solves’ the TOS for 10 citys in about 1000 steps while ‘learning’ with each try.
See it in action or view a rendered image.