Help me finding a way in coder rankings

I am a coder at division 3. I wanna become better. So I decided to practise the problems in division 2 and 3 for better. But sorrowfully I don’t understand the problem named as “bad luck”. Will you give me some advise on understanding the problems?
As they do not contain video editoreals, it seems hard to me to understand. So what should I do to upgrade my problem understanding skills? Please provide me some advise…

Your first milestone should be becoming 3*, meaning to leave Div. 3 and get to Div. 2. Problem BADLUCK is of medium difficulty, which may sound reasonable, but the simplest way to put it is that CodeChef difficulties are non-descriptive and misleading to some extent. Medium problems are designed to have a solve rate of 5-10%. So this means that at best 30-40 people in Div. 1 will solve the problem and trust me with such a solve rate those are very hard problems.

So for now focus on problems tagged as cakewalk, simple, and easy. You can spice things up with some easy-medium problems but even these can be challenging for Div. 1 and the vast majority of Div. 2 participants. CodeChef Starters series contains a nice problemset of all these difficulties, so in my opinion start with the latest Starters 7 and work your way towards the very first Starters.

Another important tip is not to rush to the editorial when you get stuck on a problem as what you’ll encounter will mostly be problems with an easy solution after you spot some property. It’s okay to move on if you are stuck with no ideas for about 30-40 minutes, but try to really put yourself into it during that time span.