- Problem 1 with hints
- Problem 1 with extended hints
- Problem 1 with even more hints
- Problem 1 with very many hints

The best solutoin awards [bonus factor exp(1/3)] goes to all those who managed to find an exact solution:**Siddharth Tiwary****Diogo Netto****Cem Arda Tepe together with Artun Bayer** (total points will be divided by 2.) This exact solution deviates from what I had in mind, and is based on a research paper (cited properly). What is noteworthy is that the answer is actually precise and not dependent on the assumption L>>r.

Apart from these, here is a minimalistic solution (non-exact estimate) by **Kaarel Hänni **(this earns him a bonus factor of 1.1)