This is my personal note and might be some kind of user editorial/learning material for some people!
This is the first episode of this "note" series. I will write notes on problems (normally around 2400-ish problems), which are completely solved without looking at the editorial, that are both interesting and educational. I normally will spend a few hours on each problem so please be patient when reading the blog. The problem on these notes should give a very interesting solution and will likely be optimizations problems (I feel like these problems have an IOI-style, which requires you to find some incomplete solution first then find the final solution using it).
If you want to motivate me to write a continuation (aka note 2), a significant upvote from you would be well appreciated! If I received lots of downvotes (because I'm also spending a lot of time to write this and to learn latex only to express my ideas accurately to you guys), I'm probably not gonna continuing writing these blogs.
Problem link: ABC133F
Try to solve the task independently before continuing the blog.
That reduces the problem to $$$O(N ^ 2)$$$, lets optimize it!
This allows an $$$O(N log N)$$$ solution
Feel free to ask anything about the task. I will try to respond them if I am free.