inTemp's blog

By inTemp, history, 7 weeks ago, In English

Is it just me or is anyone else wondering that nowadays Codechef Cook-offs and Lunchtimes are becoming better than codeforces contests.

They are more diverse and involves a lot of thinking and are more fun to solve. There are questions on all topics like Probability, Combinatorics (which is becoming a rarity in codeforces contests nowadays) as well as Data structures.

Less server issues, no queue and good quality questions.

I liked todays(Codeforces Round #660 (Div. 2)) contest as it was diverse but comparing recent contests Educational Codeforces Round 92 (Rated for Div. 2), A-E are mostly ad-hoc problems which are fun sometimes but not when overdone.

What are your thoughts on this?

P.S: These are the views from a perspective of Div2 participant on Codeforces and Div1 on Codechef. I feel that Div1 Codeforces particpants might not agree as they get diverse contests frequently in comparison to Div2 particpants.

 
 
 
 
  • Vote: I like it
  • +70
  • Vote: I do not like it

»
7 weeks ago, # |
Rev. 2   Vote: I like it +45 Vote: I do not like it

I also don't like ad-hoc problems. However, it might be the easiest type of problems to prepare for the contest. Coordinators quite often reject problems requiring other techniques as too standard. It is hard to come up with the original problem, requiring the usage of traditional algorithms.

  • »
    »
    7 weeks ago, # ^ |
    Rev. 2   Vote: I like it 0 Vote: I do not like it

    Why would ad hoc the easiest to come up with?

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it -8 Vote: I do not like it

      Well, not easiest to think of, of course standard types are easier to think of, but they are better for contests because over time ideas have already been taken and problems need to become increasingly creative.

»
7 weeks ago, # |
  Vote: I like it +5 Vote: I do not like it

what are ad-hoc problems?

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +21 Vote: I do not like it

    They are problems which don't require knowledge of any specific data structure or algorithm (you can't put them into some category). And, in most cases, their solution can't really help you in other problems. (the logic you apply for an ad-hoc problem is usually useful only for that problem)

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it -40 Vote: I do not like it

    In the most simple terms it means, either you get some weird thougth/guess that this might be the solution and try it. If its AC, you are good to go, else scratch your head for the whole contest

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +157 Vote: I do not like it

    Problems I cant solve.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +7 Vote: I do not like it

    Problems that decrease my ratings.

»
7 weeks ago, # |
  Vote: I like it +17 Vote: I do not like it

I agree, the only thing wrong with codechef is its long challenges...

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +41 Vote: I do not like it

    The comments section of codechef annoys in form and content, too.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it +5 Vote: I do not like it

      Yes, they need to improve on their forums.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it -17 Vote: I do not like it

    Yes, I also see a lot of hate is given to codechef because of frequent cheatings in long challenges.

    But in short contests, its difficult to cheat comparitively plus the quality of questions is good and more diverse

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +4 Vote: I do not like it

    Also in recent contests test cases are weak in one of the problem. Codechef need good testers.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +84 Vote: I do not like it

    What is wrong with long challenge?
    Unethical behaviour of participants isn't the fault of CodeChef.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it +35 Vote: I do not like it

      Atleast someone's smart here.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it -17 Vote: I do not like it

      Its like saying what is wrong with android security hackers in existence is not Google's fault.. I never said long challenges are unnecessary but the implementation is a problem. Also cheating is not the only issue here people with too much time to spare come at top and when we are talking about 5+ days it matters. My suggestion- give 2 ratings one for long one for others.

      • »
        »
        »
        »
        7 weeks ago, # ^ |
          Vote: I like it +37 Vote: I do not like it

        with too much time to spare come at top

        In my opinion, it is an advantage of long. Have you even spend a day thinking on a single problem? I bet you rarely do this on codeforces. But long forces you to do this. It's an important thing required for further development. I skipped the last 10 longs and I regret it. Because that was the reason for the rise in my development. When did you last time come across a problem which needs 1 day for just coding?

        Instead of just hating it look at its advantages.

        Even if long has 1000 disadvantages. There are 1000 advantages of long, which I will choose over those 1000 disadvantages. No one is forcing you to participate in longs. You can just choose in short contests only. In the long run, your rating will remain same (at an equilibrium) even if you participate in 2N/3 contests instead of N contests.

        My suggestion- give 2 ratings one for long one for others.

        You never gave any suggestion. You just wrote a simple statement that everything is wrong with codechef longs.

»
7 weeks ago, # |
Rev. 2   Vote: I like it +14 Vote: I do not like it

Since CodeChef organises just 2 official short contests, they have to be of good quality. I hate the forum thing on CodeChef. They should maybe use the posts/announcement section of CodeChef for the contest to keep the participants updated about the editorials rather than the forum.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    They do actually. They post on codeforces blogs for the announcement of contests but since it is not an "official" announcement it is not shown in Home page of codeforces.

    One thing that I feel is Codechef can start organizing more than 2 official contests. That way they can have more active participants and we will also get good contests.

»
7 weeks ago, # |
  Vote: I like it -114 Vote: I do not like it

CF is out of ideas. So they make stupid AdHoc/constructive problems. You won't learn shit from Codeforces these days... Better switch to Atcoder and Codechef. It's Much better.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it -32 Vote: I do not like it

    They are not shit. They have just become too monotonous for us to see same types of questions coming in every contests.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it -68 Vote: I do not like it

      Yea dont take it the wrong way...

      I think Changing the coordinator should help with this problem. Other people should also get a chance.

      • »
        »
        »
        »
        7 weeks ago, # ^ |
          Vote: I like it +1 Vote: I do not like it

        bruh your username LMFAO. dont hate the game tho my guy, maybe codeforces being more adhoc makes it unique and harder purposefully

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it -20 Vote: I do not like it

    I don't think CF is out of Ideas. I think ad-hoc problems are harder to come up with (for authors) compared to more topic based problems.

»
7 weeks ago, # |
  Vote: I like it -16 Vote: I do not like it

Agree!!!

»
7 weeks ago, # |
  Vote: I like it -13 Vote: I do not like it

Agree, but from last few contests , it seems like Codeforces is improving . Even yesterday they have 2- graphs problems , etc.

I agree Codechef short contests are much more educational , whereas Codeforces are competitive .

»
7 weeks ago, # |
Rev. 3   Vote: I like it +2 Vote: I do not like it

When Codechef Div-1 contests are hard people say it's unbalanced and when we are able to solve few questions in Div-1, we say now it's good and balanced.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +4 Vote: I do not like it

    You could be right. But I don't think this is actually the case. I didn't see much change in the number of questions I am able to solve. Earlier it was 2, now its 2(mostly) and 3(sometimes).

    My point is that generally I find codechef contests to be better because of more diverse questions. Seeing same sort of questions again and again could be frustrating. Cook-offs and Lunchtimes don't have repetitive concepts.

    Proof
    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it +8 Vote: I do not like it

      I agree to the fact that Codechef problems are new and are really based on data structures and cover vast range of topics. I feel that solving Codeforces requires practice and brain because Ad-hoc problems require a lot of brain storming.

»
7 weeks ago, # |
  Vote: I like it +14 Vote: I do not like it

In Educational Round 92 B was dp and E was Maths.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it -9 Vote: I do not like it

    You might have done B by using DP but the intended solution was greedy and was an ad-hoc problem. 88566966

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      All the problems need some observation, for example, problem B of EDU Round 92 could be done with DP (not ad-hoc) or greedy (which is also not ad-hoc). Normally all problems in Codeforces Rounds need some kind of observation. Problem B had a greedy solution, which is a well known startegy. So what are you complaining about? If you consider every problem which needs some kind of observation ad-hoc, and you dislike it then just quit. All the problems are like that.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it +8 Vote: I do not like it

      Lol

      greedy != adhoc

      Sorry, but I guess you don't know what does ADHOC really means, you just use this new/hype word without knowing the meaning of it

      • »
        »
        »
        »
        7 weeks ago, # ^ |
          Vote: I like it +3 Vote: I do not like it

        I might be wrong but arent ad-hoc the types of problems which require observations which are only applicable for that particular problem?

        Often those observations are implemented greedily

»
7 weeks ago, # |
  Vote: I like it +104 Vote: I do not like it

yeah cf contests is full of adhoc problems!(except the last round) but you cant say anything because Um_nik and antontrygubO_o will say that NO the adhoc is really great and im coordinator and i will say which problem is good and which one is bad(anton said that in his blog). and his high rating friends and idiot users that dont read the comment!!! and only upvote a blog/comment that has lots of upvotes or a high rating person wrote the blog/comment will support him. and its really really disgusting that so many users dont say their opinion becuase they think that they will get downvotes

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +24 Vote: I do not like it

    What I have observed that mostly Div1 participants especially above grand masters, they don't bother with this issue much because they get to see much diverse contests(in comparison to Div2) as it is relatively easy to prepare a hard Div1 problem consisting of DS and good math.

    As antontrygubO_o said in his blog that it is difficult to create an easy C-E problems which require DS and math which I agree but why create an easy contest in the first place.

    Nowadays D's are having 2000+ submissions which can be reduced up-to 800-1000 if we can just create a more diverse contests which might be of moderate level(definitely not EASY).

    Please don't say : "If you don't like Div2 then reach Div1"

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it +3 Vote: I do not like it

      mostly Div1 participants especially above grand masters, they don't bother with this issue much because they get to see much diverse contests

      Or maybe because many of them are strong in adhoc problems. Or maybe when problemset is full of problems in their weak zone, instead of complaining and demanding more diverse problemset, they want to improve their weak point (I fall in this category).

      • »
        »
        »
        »
        7 weeks ago, # ^ |
        Rev. 2   Vote: I like it +8 Vote: I do not like it

        I think you are failing to understand my point. I like ad-hoc problems. They are fun to solve. I am trying to focus on the point of having multiple consecutive contests full of ad-hoc problems.

        You are assuming that I am whining because they are my weak zone. They aren't. I am not extremely good at them but I am not bad either.

        I am focusing about having questions involving other topics as well. You tell me which was the last recent contest where we had a Probability/Combinatorics/Good DP problem from C to E and how frequent are they?

        • »
          »
          »
          »
          »
          7 weeks ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          You are assuming that I am whining because they are my weak zone.

          I never did so. But I think most complainers whine because of this reason.

          I am focusing about having questions involving other topics as well.

          My point is instead of focusing on diversity of problemset, focus should be more on problem quality. Feel free to complain if the problem is repeated / bad (easy idea, boring and long implementation), otherwise focus should be on doing better regardless of diversity of problemset.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it +21 Vote: I do not like it

      Do you count me as above grand master? I'm bothered by it as well since I'm bad at guessing these solutions leading to things like being able to solve D-E but not B-C because I failed to do the correct observations once in a while. These problems are kinda hit or miss and if there many such problems in a contest it becomes gambling.

  • »
    »
    7 weeks ago, # ^ |
    Rev. 2   Vote: I like it +18 Vote: I do not like it

    True! In one of the contest blog, Errichto came and said that "comment section is full of shit" and people really got crazy and upvoted like hell.

    No offence.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it +13 Vote: I do not like it

      That contest blog was actually shit bro! Full of memes and unnecessary comparisons between tourist and MiFaFaOvO.

      • »
        »
        »
        »
        7 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        Yeah, I know it was shit. But when I saw people upvoting the comments, it was crazy for me. That's what called an achievement.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it -23 Vote: I do not like it

    Calling people idiots who agree with their views is idiotic or maybe you are too frustrated because you are failing to increase your rating without "your-type" problems.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it +58 Vote: I do not like it

    Except that you can say anything, and coordinators are reading your complaints. But I guess my blog shows that it is not that one-sided as comments under round announcement make it seem. There are people who like ad-hoc problems, and there are people who like boring standard data structure problems.

    And yes, significant part of coordinator job is "say which problem is good and which one is bad" so... what are you dissatisfied with? Do you want a system where anyone can come to coordinator and say "here are my 5 problems, they are great, balanced and not well-known, you prepare them"? I guess you are saying that coordinator's taste is very different from yours. Well, you can't do anything about it. You can try to became a coordinator yourself, but I somehow doubt that it will be a huge success.

    I'm not a coordinator, have no affiliation with CF and certainly don't have a say in choosing problems for rounds except those I prepare or test (to some very small extent).

    • »
      »
      »
      7 weeks ago, # ^ |
      Rev. 3   Vote: I like it -6 Vote: I do not like it

      I do like ad-hoc problems but I am just finding them a lot more frequently than before. Making rounds with same pattern every now and then just makes them boring now.

      And if grandmasters people find Data structure problems boring, we haven't had a Probability/Combinatorics/Good DP problems since a long time.

      Being a coordinator is a difficult task and I can't be one. I know too less.

      But saying to become a coordinator oneself for solving this issue is IMO merely just ignoring it. comment

      Sorry for my poor English!

      • »
        »
        »
        »
        7 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        same pattern every now and then

        Can you show us some adhoc problems with repeated pattern except Div2 A,B? I see similar patterns in probability/combinatorics/DP/DS much more frequently than adhoc problems. Solve 300 good problems in each of these topics and you will see similar patterns too. That's part of the reason why many experienced contestants (including me) are specially weak in adhoc compared to other topics (and many people want more diverse problemset mostly because they don't like too many problems in their weak zone).

        • »
          »
          »
          »
          »
          7 weeks ago, # ^ |
            Vote: I like it -8 Vote: I do not like it

          If I solve 300 good problems of each topic then why would I be in div2? div2 rounds would be prepared in such way that standard for div2 problems would be eliminated. But, if you see antontrygubO_o most probably eliminates standard for div1 problems too.
          div2 round has nothing wrong with adhoc problems, nor wrong with some standard for red problems as long as it doesn't just say find diameter of tree.

          • »
            »
            »
            »
            »
            »
            7 weeks ago, # ^ |
              Vote: I like it 0 Vote: I do not like it

            If I solve 300 good problems of each topic then why would I be in div2?

            That's a bold assumption. 1082G - Petya and Graph is an example of repeated problem, the problem is just a rephrase of existing problem (read editorial), but not many people solved it in contest. I doubt if problemsetters want to create / give repeated problems in CF except for educational rounds.

            if you see antontrygubO_o most probably eliminates standard for div1 problems too.

            How do you know it? I have no idea which type of problem Anton rejects and why, but I doubt that he has valid reason otherwise we would probably see problemsetters complaining more.

        • »
          »
          »
          »
          »
          7 weeks ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          There is a misunderstanding. By "same pattern" I didn't mean to say questions having repeated concept, I am talking about the same type of contests i.e., multiple consecutive contests full of adhoc problems

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it -9 Vote: I do not like it

    I like adhoc, I hate last non-adhoc round.

»
7 weeks ago, # |
  Vote: I like it +31 Vote: I do not like it

According to me , Codeforces problem are more of brain twisting . you can just compare A of codechef with A of codeforces , you will find A of codeforces more harder than codechef A type. also range of question vary alot in codeforces (problemsetters are always very good coders).

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    If you have been doing Codeforces for a long time then you really can't say this because you and me both knows how to solve A within few minutes.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Yes , you are right but if you compare codeforces and codechef , you will find people became 3 or 4 star on codechef and still newbie in codeforces .

»
7 weeks ago, # |
  Vote: I like it +9 Vote: I do not like it

I think I am the only person in this world whose codechef rating is less than codeforces rating. (I am 3 star on codechef ;_;)

»
7 weeks ago, # |
Rev. 3   Vote: I like it -43 Vote: I do not like it

only reason cf has more public than any other platform is because of number of contests . If codechef also makes 10 short contests per month , it won't be behind codeforces .Understood my friend antontrygubO_o ?

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    making 6-7 contests in a month alone is a challange in my opinion.

»
7 weeks ago, # |
  Vote: I like it -27 Vote: I do not like it

yes i agree codechef is better than codeforces in term of quality of questions.

»
7 weeks ago, # |
Rev. 2   Vote: I like it 0 Vote: I do not like it

don't know which one is better....but i think codeforces is far ahead of codechef but cook off and lunch time are very fun to solve and yes it covers many topics .....but as many top coders participate in codeforces,it is very much hard to maintain good rating in codeforces where in codechef in div 2 it is not hard to increase rating......people should try to participate in those two contests........another good fact about codechef is codechef doesn't make their plagiarism submission skipped,penaltized the user.............

»
7 weeks ago, # |
  Vote: I like it +9 Vote: I do not like it

Codeforces is far better. In codechef you immediately get what to do in even medium problems. In codeforces, you have to think out and find out an approach.

  • »
    »
    7 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Just a question, what rating range on Codeforces do you think would Codechef medium problems belong to?

»
7 weeks ago, # |
  Vote: I like it +178 Vote: I do not like it

[---] Div1 Codeforces particpants [---] get [---] contests frequently [---].

?????

»
7 weeks ago, # |
  Vote: I like it +26 Vote: I do not like it

In an ideal world, I think the CodeChef Long Contest is the superior format. I learned a lot of techniques by participating in CodeChef Long, and I was rewarded for persevering, brainstorming, and researching. I'm not a fan of how the most difficult problems can sometimes boil down to "According to this research paper...", but it's not like I'm going to solve the Div1E in Codeforces anyway. There's also the huge issue they face with cheating and plagiarism and---well, yeah, I did say "In an ideal world".

Short format contests can sometimes feel like luck of the draw on Codeforces. I can tell you that I only reached Master because of speed during one of the Global Rounds. I think the time limit is too short and ends up rewarding memorization more than it necessarily should, and also it stops us from seeing nice but difficult implementation/data structure problems.

»
7 weeks ago, # |
  Vote: I like it -11 Vote: I do not like it

I believe this is mostly due to the number of contests CF is pushing. I see it this way — We get two rounds to practice our ideas and general thinking (with 2-3 algo problems, mostly hard ones) and then we get a round with some math + algorithm.

I see this as a good thing for beginners, but don't know about more experienced coders. E. g. I have participated in only 3 rounds (2 of which ended up unrated) and solved 3 problems in each of them. Out of those 3 problems, all of them were construction problem which required me to think and use paper. Problems which I didn't solve were DP/Graph algorithms that are generally popular, so I had a chance to brush up my common algorithm skills. I believe this makes the contests less overwhelming and much easier to perform well for beginners (you won't gain rating, but at least you will solve some number of problems (4-5/7-8 or 3/6) and not end up having solved 1 or at most 2).

I hope my points are clear.

  • »
    »
    7 weeks ago, # ^ |
    Rev. 2   Vote: I like it +35 Vote: I do not like it

    I don't understand why solving 2 problems as the normal amount is so bad. For most of my yellow life 2 problems was the normal amount to solve during a round (I mean Div. 1 only rounds). I actually dislike the contests where I'm expected to solve 6 or whatever problems because it's so easy to get tripped up by some annoying easy problem.

    Furthermore the amount of interesting (appropriate for my level) problems has never been more than 2 (and often it's 1 or 0). Other problems are either too easy or too hard.

    • »
      »
      »
      7 weeks ago, # ^ |
      Rev. 2   Vote: I like it 0 Vote: I do not like it

      I was referring to the Div 2/3 contests, not Div 1, so I hope it clears things up a bit. I think it is too harsh for people to see they solved only 2/7 problems in a round for a beginner. It's even worse if they see "no progress" in months, which is not a result of their poor progress but the diversability of the third or fourth problem, so they end up thinking they have stayed at the same level.

      I agree with your second point. Either a problem is too easy/too hard in most of the cases.

      • »
        »
        »
        »
        7 weeks ago, # ^ |
          Vote: I like it +6 Vote: I do not like it

        I was referring to the Div 2/3 contests, not Div 1, so I hope it clears things up a bit.

        IMO it doesn't really matter. I just don't think it's an inherently bad thing that most people only solve a small number of problems in a contest.

    • »
      »
      »
      7 weeks ago, # ^ |
        Vote: I like it +45 Vote: I do not like it

      the amount of interesting (appropriate for my level) problems has never been more than 2 (and often it's 1 or 0)

      Couldn't agree more with this, for me it's 90% of the times just 1 problem, the rest are either trivial to me or impossible for me. It has been this way since my day 1 till now.

»
7 weeks ago, # |
Rev. 2   Vote: I like it +28 Vote: I do not like it

Why are we comparing these two???

I know I am new in this platform....but maybe i think it's not necessary to compare these two......maybe both of these have many complaints of their user.....Someone says Codeforces is better someone says Codechef is better..But the fact is both Codedhef and codeforces are helping for our skill developments.... Thanks both codeforces and codechef............................................................ ...........................Just express what I thought(sorry if I write somthing wrong or stupid).......

»
7 weeks ago, # |
  Vote: I like it +6 Vote: I do not like it

Registered at codechef after this blog. Need to checkout their problems

»
7 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

I don't understand, is there any rule that says "You can only play contests on codechef or codeforces but not both". Both of the platforms are very good. Both have their own pros and cons. I have used both of this platforms from 1 years and i have learned a lot from codechef andcodeforces together. The co-ordinators always try to set best, unique, conceptual questions. We should give respect to them.