Below, you can find a hint for the Challenge. Actually, it is only the first hint of a sequence of hints, spread out over a chain of separate web pages.
The hints are now fairly complete, together with some afterthoughts and a summary at the end.
There are a number of discoveries to be made on the way, and it would be a pity to spoil the fun all at once. You learn more from the Challenge when you make these discoveries yourself, rather than read them here.
It may not sound very helpful, but the first hint is to read the problem statement again, carefully, and draw some inescapable conclusions from the requirements.
Next, you should make an active attempt to try some (small) programs in the machine. Your initial goal is to create something that solves a (small) part of the problem.
And then think again.
It is your turn ...
If you have no idea how to get started, or if you tried some programs and do not see how to proceed, then you are ready for the .