### Nickir's blog

By Nickir, history, 2 months ago, translation, ,

Since the first div. 3 round there were 23 of them and probably some of you noticed that the rounds have become quite difficult for their target audience -- people with rating below 1600. More and more often only 3-4 problems out of 6-7 total are really being solved by the official participants, while the rest of the problems are only solved by 100-200 people many of whom participate out of competition.

Not to be biased we can use such a tool as problem difficulty, a recent feature of codeforces. In the table below you can see round numbers, below -- amount of problems with difficulty 1600 and less in the particular round, below -- total amount of problems in the round.

Information in the right says that in average in a div. 3 round only 3.7 problems from about 7 in total have difficulty 1600 or less, which is only 55.8% of all problems of the round. Div. 3 announces allege that the rounds are going to be interesting for people with rating below 1600 and will seem easy to people with rating 1600-1899 and to people from div. 1. While in fact half of the problems of a div. 3 round are interesting to people with blue, purple and orange nicknames. So often purple guys can't really solve one or two problems of a div. 3 round.

We could compare that with statistics on educational round, that are pretty much prepared by the same people.

Round number in the first row, amount of problems with difficulty 1600 or less in the second row, total amount of problems in the third row, amount of problems with difficulty 2100 or less in the fourth row.

The statistics says, that in average educational rounds have only one easy (<= 1600 difficulty) problem more that div. 3 rounds. An educational rounds have the same problem when only 4 out of 7 problems have the difficulty of 2100 or less, which is the target audience. Last 2-3 problems of those round are only solved by a few people, mostly from out of competition.

How could we fix that?

1) Transfer too difficult problems from educational round to div. 1 rounds so that the latter ones could appear more often 2) Vacant places could be filled with too difficult problems from div. 3 rounds 3) Vacant places in div. 3 round could be filled with problems proposed by codeforces users

The more problems for the target audience are in the round, the less the difficulty gap between them. That could allow to make the ability to solve problems significant, not the ability to code fast.

• +451

By Nickir, history, 6 months ago, ,

Hej Codeforces!

So I held a city level contest at my university today But all the contestants kept getting a 403 error trying to use codeforces I guess that's because they used about 20 PCs simultaneously and those PCs have the same IP as they belong to the university's local network Any tips on how I could avoid such a thing in future contests? Thanks in advance

• +3

By Nickir, history, 11 months ago, ,

Hello Codeforces!

I would like to improve my competitive programming skills and to perform ACM-ICPC better. Therefore I need a coach for remote lessons.

My goals are to get about 2100+ of rating on codeforces and preferably to get to ACM-ICPC finals or to be close to that. Lessons in Russian would be great but English is nice too. Ready to pay up to 20-25\$ per hour.

If you're a coach or you know someone who could help me with that -- I will be really grateful to get your lessons or advice.