Good Work msa.

I suggest adding a paragraph at the beginning to tell the reader what to expect (a DS that has advantages over other Data Structures somehow — will help solve some problems easier — just a DS idea you came up with and why think interesting and want to share, ...etc).

I didn't understand the proof of the greedy algorithm in problem E from the editorial. Can someone explain it?

Deleted.

In problem H, I think the inequality $$$500\pi.r^2 - 3^r \gt 0$$$ means that the each tower should have positive contribution, why is this true? Can't some towers make up for others for examples?

How did you calculate the maximum cost?

It depends on how cache-friendly your operations are and how much can the compiler cut out from your branching

Would you elaborate more on this part?

https://codeforces.me/enter?back=%2F : 8ba2f4aea8bc0f6e : just tried to login

https://codeforces.me/profile/MahmoudBassem

I think it is better with spoilers, and code.

for D, why do we need a base case in DP ? How could it happen that we enter a node twice?

"add it or subtract depending on the parity of the cardinal of the subset (this comes from inclusion-exclusion))." Can u please elaborate more on this part?

Can anyone elaborate how would we drop the third parameter if we compressed the array in the first solution of D?

This is elegant!

Can anyone explain why the transitions are done that way in D? I thought that we should add f0[y] to f0[x] so that x's parent knows the amount of zeroes after x, but why would it need to know how many ones came after x?