AoC 2020 - Day 3: Toboggan Trajectory

And we start with maps :-)

With the experience of previous years, it was not a difficult task. The final solution is smaller than the previous day, even if it required a bit more programming.
However, it took me a bit too much time than I was expecting. Eventually, I had to debug to discover a silly off-by-one mistake. I suspect the decision to wake up earlier to work on the problem had an impact on my performance :-)

I like having decided to use a generator for representing the function. It made the solution much nicer to see, and the second part almost a breeze.
Also, I have learned a nice new corner of python 3.8: math.prod.