JasonKouyl's blog

How can I have the ability to Div.2C in every contest?
By JasonKouyl, history, 5 years ago, In English

I've joined Codeforces 4 months ago. The first goal I set for myself is becoming a blue coder. But after I've taken part in some contests I found it's not so easy. I've taken part in 9 contests and my current rating is 1363. In Div.2 contests I can averagely solve 2 problem. But I sometimes haven't got any ideas for problem C! And when I'm analyasing how some of my friends (tzc_wk, i_wanna_bao0_pj) became blue, I found that they have one thing in common: they all have the ability to solve Div.2C. So it seems that to become blue I should have the ability to solve Div.2C. But what problems should I do? With what level of difficulty? What kind of algorithm? Greedy, graphs, DP, math or something else? I'm really confused.

  • Vote: I like it
  • +29
  • Vote: I do not like it

Comments Comments (33)
| Write comment?
»
5 years ago, # |
  Vote: I like it +47 Vote: I do not like it

The problems you manage to solve in-contest tend to be a step down in difficulty from the hardest problems you solve in practice.

→ Reply
  • »
    »
    4 years ago, # ^ |
      Vote: I like it +4 Vote: I do not like it

    Is the implication that it's better to practice on Ds in order to solve Cs in-contest? Or just that you should be realistic that if the hardest problems you're solving in practice are Cs then you will not be guaranteed to solve them in-contest?

    → Reply
    • »
      »
      »
      4 years ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Nowadays I am solving only D problems from A2oj.So just asking is it more beneficial than solving in a particular rating range?

      → Reply
    • »
      »
      »
      4 years ago, # ^ |
        Vote: I like it +19 Vote: I do not like it

      I think both things are true. Harder problems teach you new perspectives and force deeper understanding which later lets you kill easy problems quickly.

      → Reply
»
5 years ago, # |
  Vote: I like it +5 Vote: I do not like it

look. try to open, say 250 div2 contest and start solving from there every C problem. 592 — 250 and you have 342 C already solved problems. But first, read this shit

→ Reply
  • »
    »
    5 years ago, # ^ |
    ← Rev. 2   Vote: I like it +15 Vote: I do not like it

    Bad advice. As saketh said above solve D-E in practice to solve C in contest.

    → Reply
»
5 years ago, # |
  Vote: I like it +6 Vote: I do not like it

What helped me come out of Div2 A and B was learning new things.

I learned dfs, bfs, and solved a lot of greedy problems. I learned very frequently used data structures such as segment trees. I solved some good problems on binary search. Learned a bit about primes as well.

I guess this was enough for me to solve Div2 C, and sometimes Div2 D as well.

Obviously, solving good(higher in rating) problems in practice helps.

→ Reply
»
5 years ago, # |
  Vote: I like it 0 Vote: I do not like it

Read this. https://codeforces.net/blog/entry/69100

Also, there is no easy way to become blue. I do CP about 2 years and still blue

→ Reply
  • »
    »
    4 years ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    But just recently you became master congratulationsss

    :O is it the lockdown training XD

    → Reply
    • »
      »
      »
      4 years ago, # ^ |
        Vote: I like it +12 Vote: I do not like it

      Thanks. Now I can say that there is no easy way to become master :D

      → Reply
      • »
        »
        »
        »
        4 years ago, # ^ |
          Vote: I like it +1 Vote: I do not like it

        Does an Algorithms course help more than 200/300 problems from the MOSTAFA junior sheet?

        → Reply
        • »
          »
          »
          »
          »
          4 years ago, # ^ |
            Vote: I like it +14 Vote: I do not like it

          I don't know what MOSTAFA means

          → Reply
          • »
            »
            »
            »
            »
            »
            4 years ago, # ^ |
              Vote: I like it -10 Vote: I do not like it

            good for you!

            → Reply
          • »
            »
            »
            »
            »
            »
            4 years ago, # ^ |
              Vote: I like it 0 Vote: I do not like it

            https://codeforces.net/blog/entry/65133 this one? basically doing lot's of problems vs algorithms course

            → Reply
            • »
              »
              »
              »
              »
              »
              »
              4 years ago, # ^ |
              ← Rev. 2   Vote: I like it 0 Vote: I do not like it

              i choose lots of problems!!!! I really like these problems and i used to do many hard problems daily but my exams are going on and i m also preparing for a civil service exam so i don't have enough time now.but i really want to become atleast candidate master before sept!!

              → Reply
              • »
                »
                »
                »
                »
                »
                »
                »
                4 years ago, # ^ |
                  Vote: I like it 0 Vote: I do not like it

                Wow!

                Thanks and also, All the best!

                btw do we have coding positions in UPSC or it's for your passion?

                → Reply
                • »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  4 years ago, # ^ |
                    Vote: I like it +1 Vote: I do not like it

                  na na there is no such position i just like it!! (addicted)

                  → Reply
»
5 years ago, # |
  Vote: I like it 0 Vote: I do not like it

Solve +1500 difficulty problems ( In my opinion ) and start learning more advanced DS and algorithms

→ Reply
»
5 years ago, # |
← Rev. 2   Vote: I like it +6 Vote: I do not like it

I analyzed your profile using Codeforces Visualizer and Code Drills it seems you haven't really solved much C problems.

Use this link to solve codeforces C problems sorted by difficulty and trust me you will start seeing improvements after solving about 50 problems, I am also using it and I solve a minimum of 3 div2 C problems every day (sometimes try practicing div2 D problems too).

I have started noticing improvements too, matter of fact I just became 4 stars on codechef and I know it isn't much of an achievement but I'm proud of it :) all thanks to these div2 C problems I solve every day, it's the only form of practice I've been doing for a month now.

Also, try solving A and B as fast as possible during contests, it gives you time to think about the C problem and sometimes it puts you in a good rank already during the contest.

EDIT: Try disabling tags too, it helps.

PS: We can practice together if you don't mind :)

→ Reply
  • »
    »
    5 years ago, # ^ |
      Vote: I like it +2 Vote: I do not like it

    Well, it seems that more and more people are able to solve div 2 problem C (in contest) nowadays. So even you can solve problem C in contest, unless you can do it very fast (within first 20 to 30 minutes, that's not likely to get you in a very good rank.

    → Reply
    • »
      »
      »
      5 years ago, # ^ |
        Vote: I like it +1 Vote: I do not like it

      It will at least get you to the rank of specialist, which would still be an improvement for the OP.

      → Reply
  • »
    »
    5 years ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    D is the new C as no longer we get 5-problemset format contests.

    → Reply
»
5 years ago, # |
  Vote: I like it 0 Vote: I do not like it

Solve problem D with DP or graphs

→ Reply
»
4 years ago, # |
  Vote: I like it +15 Vote: I do not like it

To become true blue, you have to solve Div.2D consistently:)

→ Reply
»
4 years ago, # |
  Vote: I like it 0 Vote: I do not like it

I couldn't figure out today's Div2C :/ I guess sometimes D and E are more doable than C (i.e. if you are stuck on C, it shouldn't hurt to look at later problems).

→ Reply
»
4 years ago, # |
  Vote: I like it +1 Vote: I do not like it

JasonKouyl Since you are blue now, please share your journey.

→ Reply
»
4 years ago, # |
  Vote: I like it 0 Vote: I do not like it

Hi here I have a question about my future.
I've been in OI for nearly 3 years but the result of OI isn't very good. And I can only get in No.3000 — 6000 in CF rounds(See my another abandoned account Eason_AC). What should I do for the future? I feel very confused about my future now. :(

→ Reply
  • »
    »
    4 years ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Practice regularly by solving problems of slightly higher difficulty than your rating. Learn to analyze time complexity and the big-O notation.

    → Reply
»
3 years ago, # |
  Vote: I like it 0 Vote: I do not like it

You're blue now!

→ Reply