algofighter's blog

By algofighter, history, 6 weeks ago, In English

When you solve a problem (on your own or after reading the editorial), then you are able to solve a problem again in the same or shorter time than previously? Do you solve some problems 2nd time after some time to remember some techniques or algorithms (like BFS, Dijkstra, etc.)? Even when I solve a problem on my own, after some time, I forget a solution fast and I sometimes can't solve a question again.

 
 
 
 
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5 weeks ago, # |
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Depends on the problem in my opinion. If it was a hard problem, and you really struggled with it, you will mostly remember it if you see it again. If it wasn't really hard, but had some interesting observation, you likely noted that observation / style of thinking in your subconcious, so you don't really remember the problems as such, but the ideas / thoughts / tricks. And knowing some trick already, if you see a problem which requires it, you will likely solve it faster than you previously did, without knowing the trick.

If you have trouble solving some problems again, you should try to break down the problem and your approach. And think of what parts you have difficulty coming up with on your own. It should help to understand the concepts / idea better.

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    5 weeks ago, # ^ |
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    This reminds me of the following quote from the book "Faust Versus Mephistopheles?" by Kim Smirnov.

    “Today the formation of the personality­ involves the overcoming of difficulties, the some­ times agonizing search for answers to problems, and the independent solution of formidable tasks. You probably know this from your own experience. What school assignments generated the most interest, which ones do you remember to this day? The ones that were hard to solve, the ones which took a long time to work out. Those which are tackled easily frequently do not stick in our memory; they groom neither the mind nor the will. I once had to decipher a manuscript of Dmitry Mendelyev. We deciphered thousands of notes. But I particularly remember one of them. And it was by no means the most impor­tant. But we had worked hard on it for probably a year... ”

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5 weeks ago, # |
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I remember all the standard DS/Algo problems. But when it comes to adhoc, I feel like I forget the approach after sufficient time has passed. So I feel like, I'd solve the same adhoc question with similar(maybe a little faster) speed if I see it after a long time.

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5 weeks ago, # |
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No.

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5 weeks ago, # |
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It depends on the specific people. For example I have a very good memory for problems which I have solved/seen (we sometimes joked that in our ACM team Marcin_smu takes care of solving, mnbvmar takes care of coding and I take care of remembering), but some people don't. For example we often make jokes about Errichto about how his memory is so terrible, he and his teammate once virtually participated in an ACM contest that they solved ~3 years earlier and they didn't even realize that.

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    5 weeks ago, # ^ |
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    Finally, a comment where it looks like you people really know each other. Everywhere else, you all talk like complete strangers to one another and leaves me wondering, aren't they from the same university?

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      5 weeks ago, # ^ |
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      I think our group conversations on messenger total to probably something over 300k messages xd. The only sad thing is that they absolutely ignore tons of memes I send them, Xellos would probably be a better friend in that regard :p

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        5 weeks ago, # ^ |
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        Then it depends, if the majority of them are memes then I think they are already better friends as they didn't leave :p

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          5 weeks ago, # ^ |
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          mareksom left the conversation (and this country) because we spammed too much :(

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    5 weeks ago, # ^ |
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    3 years might be okay. But imagine a situation where Errichto actually gave me and 10 others(top 6 in Egypt and top 5 in Saudi Arab) for the IOI camp for around a week. That was only 2 months ago and he didn't remember that xD:

    He remembered that he saw my profile picture and username before though xD.

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      5 weeks ago, # ^ |
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      Wait, what? We had an online camp (without cameras for participants) and you're surprised that I don't remember your face? I don't see how "2 months ago" matters in that case.

      What I said about mapping means: even for onsite camps, I don't remember discord nicknames of people in the camp and I think it's quite normal. I mostly remember real names after several days (it helps if they are Polish or English though).

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        5 weeks ago, # ^ |
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        Yep, that is true. In fact, I was only joking. If it was anyone else, he would also not remember.

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5 weeks ago, # |
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It depends on different kinds of problems. For instance, I am good at counting problems so I usually have a good memory of counting problems. But bad at dp etc.

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5 weeks ago, # |
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How often:

  • do I remember the statement? 100%
  • do I remember the idea / algorithm / ds that should be used? 80%
  • can I reconstruct the solution in no more than 5 minutes? 70%
  • can I reconstruct the solution in no more than 30 seconds? 30%

I've created a google form with these questions.

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    5 weeks ago, # ^ |
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    22 answers, here are the average results

    How often:

    • do you remember the statement? 75%
    • do you remember the idea / algorithm / ds that should be used? 72%
    • can you reconstruct the solution in no more than 5 minutes? 61%
    • can you reconstruct the solution in no more than 30 seconds? 35%
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5 weeks ago, # |
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Not only problems but also people:(

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5 weeks ago, # |
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In my last round, I copypasted E and got +150.

The round before that, I remembered that D was from TCO17, which I don't even know the solution, but modified a code from the problem setter to get AC.

I feel that I've only become better at memorizing problems. But my rating goes up either way, so who cares.

Also memorizing a lot of problems are very helpful for problem preparation, because you can better avoid notorious coincidence.

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5 weeks ago, # |
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Not always. There are some problems that I forget how to solve because it was intricate for me to come up with a solution, because of nasty code or because many corner case. If I enjoyed the problem, or if the solution is something more manageable to me, then I'll probably remember it.

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5 weeks ago, # |
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For me it depends on how much I learned from that question.

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5 weeks ago, # |
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I even can't remember my solution to problems which I solved 1 month before :(

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Not only that, but I remember when other people that do virtuals with me had seen that problem and not solved it during contest/upsolved it so I make sure to remind them that they didn't solve a problem they've seen before right after the contest.

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It depends on the topic you are referring to...like for example dp...I remember only classic dp problems and how to make transitions, observe states, write base cases fast etc. Any dp problem can be tackled like that. For graph theory I remember all the basic and intermediate algorithms. Challenging topics like DSU and Segment tree..I did it from EDU and remember all the approaches. I tend to mess up on adhoc sometimes. So it depends on remembering the approach and practicing questions more topicwise. So no I dont remember the whole solutions. I must say I used to believe that remembering the whole solutions would make me better and indeed I did, when I started CP..but it just makes you weary. Enjoy and embrace every problem you solve thats it.

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5 weeks ago, # |
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i memorize some problems that has tricky solution or important alogrithm

but that's all

i count on the hand that i resolve that problem.

what the stupid i am !

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5 weeks ago, # |
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Do I remember solutions to previously solved problems? Pathetic. I'm always scared that I will forget my own already used problem and I will propose it again.

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Once I was participating in a gym contest with my team, the problems were from a local ICPC contest in our country, I kept struggling with some problem. Eventually I found out that I am the author of this problem :D

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    5 weeks ago, # ^ |
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    That's so hilarious XD. What was your team's reaction when they found out you were struggling with your own problem? XD

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i forget most of the problems that i solved like 10 minutes after contest.

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You guys remember the questions you solve?