Hi Codeforces,

According to this blog post, the one with the same rating as the difficulty of the problem will have the probability to solve the problem of 1/2. So I want to ask that How hard should practice problem be? in order to know about What is the proper difficulty range for one to solve comparing to his rating?

To improve, I think +300 — +500 of your rating is good (for newer problems). For older problems, it should be something like +100 — +300 of your rating.

The more interesting question is: how hard should a practice problem be. If you know the answer, you can also figure out the "proper difficulty range" using a binary search: pick a problem, if it is too hard you know an upper bound to the proper difficulty range, etc.

That's a lot better, Thanks!

I figured out a way at least for the range of specialist and expert I think. When my rating was 1500 I started solving problem with difficulty 1600 without applying any other filter and solved 60 problems from it and as I did it I became very much comfortable with problem with difficulty 1600 and my speed also increased with it and then after doing 60 problems I moved to 1700 solved 50 problems in it and then 1800 and by the time I almost solved 50 problems in 1800, I became candidate master for the first time . It was a big thing for me as in just 2 months this practice method helped me to go from specialist to candidate master ( i think it's quick because before I struggled a lot just to become expert). I think doing 50-60 problem in a particular difficulty range exposes you to all the different kind of problems you can encounter in a particular difficulty range and also increases your speed a lot. On the other hand, if you solving problems of too much high difficulty helps too but in general, people don't have enough speed to get time to solve that problem so I think increasing speed is also as imp as learning new things and this method helped me to do it in an efficient manner.

I don't know if this method works for a higher rating or not, so views from masters and grand masters will help me too.

Edit:-link this website will help you keep track of how many questions you have solved of a particular difficulty and particular tag

Did you do the practice problems within a time limit or did you just do it until it gets solved?

I follow the method said by errichto in many of his videos i.e. keep trying a problem till you have any idea on how to solve it and only see the editorial when you are stuck for 10-15 min.

Okay. Thank you. I will try the same way. Targe CM in 2.5 months!