In the latest months, I've been dealing with interviews from multiple companies. In these, I was frequently asked complex probability brainteasers, which are however quite easy to solve using generating functions, so I thought that I could detail the gist of the method in a post, even though the method is obviously contained inside the standard reference on the matter: generatingfunctionology (Archived).

In the first months of this year, from January to April, I was in Paris for a period of study abroad at INRIA (Archived). During these months I had time to visit the city in some depth, and I would like to suggest some places to visit if you have the opportunity to stay in Paris for some days.

I realized that it was possible to create polyglot files¹ when I searched for the details of the structure of a zip file (Archived) and found that the file header in this case is at the end of the file, and thus can easily coexist within an executable file, whose headers are usually at the start.

Footnotes

1. Files that are valid in more than one format. For example, a file may be both a valid ZIP and a valid PDF (Archived). ↩