Q: You were only 8 minutes behind Tom.

This isn't a question.

Q: The first 4 problems went very smoothly for you.

Also not a question. C and D were especially easy for me because jpaulson got them early, so I knew to look for a simple solution (e.g. greedy).

Q: What were the main difficulties for problems E and F?

F was straightforward, but coding point-line distance took a while and I had to spend time finding a bug in it. I used ternary search, but maybe I should have used dot product. E took a while for me because I wasn't confident that 10,000^2 iterations would run in time.

Q: Anything to add?

You should fix Si Young's last name. It's "Oh", not "Om".