I'm currently reading this blog in order to learn Dominator Tree:

https://tanujkhattar.wordpress.com/2016/01/11/dominator-tree-of-a-directed-graph/

And I don't understand what it means by "proper ancestor". Could somebody please explain this to me?

In 2021 I was part of the team of setters and judges for my country preliminar contest. I would like to participate this year, but someone told me that if I was registered as judge for some preliminar contest, I will never be able to participate again. I haven't found that rule, what do you think?

Thanks in advance, sorry for poor english.

I'm looking forward to some day build something like a framework for training teams for ICPC, not necessarily for world finals, it could be for basic or intermediate level.

is there a complete and detailed guide on how to train a team for an ICPC competition?. if there is not and you would be the one to write it, in what would you based it on? would you adapt some methods used in other sports?

Do you think some agile theory could be applied here?