Valhalla_RL's blog

By Valhalla_RL, 42 hours ago, In English

It took me about a year to become an Expert, which may be a small feat, but I still believe that maybe sharing the resources which I personally had used might help someone.

  1. For learning algorithms: You can use a channel called takeuforward by a guy named striver: https://www.youtube.com/@takeUforward. The guy has excellent explaining skills. I would ideally recommend building a habit of reading blogs and articles, as later on, you will only have those to help you.

  2. For practice:

  • CSES Problem set: It's a very great website to practice good quality questions. The questions are sometimes standard and sometimes very unique so you ultimately end up learning a lot but the time constrains can be a bit irritating tbh. https://cses.fi/problemset/list/

  • TLE eliminators cp-31: Best one I found for rating wise practice although you will need more than 31 questions generally to get comfortable with higher rating but it does provide us with all the necessary concepts and algorithms related to that rating. https://www.tle-eliminators.com/cp-sheet

  • Codeforces Problemset: Just put in the rating you want to get comfortable in and keep on making it green until you can comfortably solve at least 8/10 problems without any help. (probably the one which will work for everyone)

  1. Always upsolve the contests and if you are unable to find you're weakness then maybe try looking at the contests where you got a negative or very low rating change and see work on the topic of the questions which you were unable to solve or solved too late.

  2. Give as many contests as you can provided you have time to upsolve them later. Some other sites where I give contests are: -Atcoder -Codechef -Leetcode

  3. Most importantly enjoy the process always remember rating is a by-product not the main goal.

  • Vote: I like it
  • +37
  • Vote: I do not like it

»
42 hours ago, # |
  Vote: I like it +1 Vote: I do not like it

Hey could you probably jot down some additional concepts you needed to solve div2 D?

  • »
    »
    41 hour(s) ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Like personally i am not able to solve div 2 d every time but from what i know you should be comfortable with data structures and algos like dynamic programming, graphs, segment trees, sparse table, ordered set etc. You can also try solving each div 2 d and if you encounter a div 2 d which you can't solve due to any concept which you didn't know maybe study that then. Also you should be good at mathematics as well. Personally I would suggest you to solve div 2 d's, solve entire dp, graphs, rmqs of cses set then 1600-1800 from tle sheet and you should pretty much be able to solve every div 2 d's from then on.

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

      Hello, to be good at math, what topics do you think will benefit us more in the long run? Can you suggest some topics in math that I should look at or maybe learn?

      • »
        »
        »
        »
        37 hours ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        Combinatorics, Euclid mathematics etc. You can google maths for competitive programming and then you can select topics and difficulty according to your rating

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

          Thank you for the suggestion.

        • »
          »
          »
          »
          »
          95 minutes ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          How would you recommend a beginner(me) who is not very good at coding(100% MEEE) to start their journey?

          • »
            »
            »
            »
            »
            »
            88 minutes ago, # ^ |
              Vote: I like it 0 Vote: I do not like it

            Ideally just learn a programming language I personally use C++ but any would do then just start practicing 800 rating then 900 and so on... getting comfortable in one rating then other and as you encounter some new data structure or algorithm because of which you were not able to solve the question just study that algorithm or data structure from somewhere.

»
41 hour(s) ago, # |
  Vote: I like it -9 Vote: I do not like it

hello thank you for this, do you also provide live help during contests? i need someone to help me when i do contests because i'm not very good

  • »
    »
    41 hour(s) ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    Nope, that's cheating. Try to focus on learning rather than resorting to such dishonest methods.

»
23 hours ago, # |
  Vote: I like it 0 Vote: I do not like it

hey

can you see my profile a bit, and help me as i manage to solve A and B quickly in div 2, but not able to solve C in it. what should i do for it?

  • »
    »
    21 hour(s) ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    how u solve b quickly it takes me good time to figure out logic for b some times i often fail to do so

    • »
      »
      »
      21 hour(s) ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      It only comes with practise, just practise questions of rating 1000 more and more and soon you will be comfortable with B

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

    It's very simple actually practice C's and practice from 1400-1600 but i guess you need to work on 1300 rating as well as I can clearly see you use AI in live contests. For the time being practice from 1300-1600 regularly upsolve contests and stop using AI in live contest and while practicing as well. Only use ai when it is taking too much time to find a bug and that also only while practicing not in live contests.

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

      Okay

      • »
        »
        »
        »
        10 hours ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        bhai nitzen mujhe bhi kuch bata de plzz like meh new hu codeforces par

        mere se 1k ke nhi ho rahe hai sawal like i am not able to apply stl !!

        ek question solve karne par bhi negative lag jaa raha hai toh abb div 2 ka b wala bhi karna hoga kuch guide kar do div 2 ka b ke liye bhi Valhalla_RL

        • »
          »
          »
          »
          »
          84 minutes ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          grind in rating 1000-1400 and study DSA like sliding window, binary search etc. Practice question b of div 2 contests and upsolve each contest.

»
15 hours ago, # |
  Vote: I like it 0 Vote: I do not like it

Why should someone go for a sheet? It's a shit mindset solving a sheet when you can explore all possible problems, every problem teaches you something! CSES and Atcoder are good in teaching you algos but to increase problem solving I am not with solving a sheet.

  • »
    »
    15 hours ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Solving more questions is important but some people just get stuck or like to solve variety of problems in that case sheets can help, I personally do both and don't mind anyone doing any of these as long as they don't cheat

»
13 hours ago, # |
  Vote: I like it +1 Vote: I do not like it

thinking if people always understood that rating is just a side effect for the experience, we would live like in the year 3025.