Kevin114514's blog

By Kevin114514, history, 3 years ago, In English

Just maybe you'll have something to ask. If not, I'll get embarrassed and shamefully delete the blog lol.

Brief introduction of myself: Chinese, 14yo.

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3 years ago, hide # |
 
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congrats on achieving lgm at 14yo

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Teach me how to reach LGM at the age of 14......

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Zhejiang province rules the CP in China? And where did you trained from? <3 Btw... Congratulations on becoming the new LGM at 14, uff ..that's so good :)

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When did you start competitive programming? How did you train ?

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    I started cp about 4 years ago or so.

    I go to school and educational institutions to do their training contests and I find problems on CF and that's that. Participating in contests like AtCoder/CodeForces regularly is useful for me.

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Hi. Could you suggest some resources to build the basic math knowledge required for cp?

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on scale of 1 to 10, how much you dislike anime?

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orz. Though I live in the United States, would you be willing to share with me some tips on how to effectively train?

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Congrats & Teach me how to reach LGM at the age of 14......

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Congrats!

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Significance of 114514 in your username?

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Congrats on hitting LGM! Just curious about your rating graph between Sep 2021 and Jan 2022 — what changed?

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    3 years ago, hide # ^ |
     
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    I was trying to solve easier problems but faster at that time. And even though I don't solve more problems than others, I can still get relatively high ranks for a Master

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Congrats on getting LGM at age 14!! Meanwhile I'm still here struggling to get purple (16yo btw)..

Do you think you will represent China at IOI sometime later in your high school? I heard that the qualifications for Chinese National Team is tough. So when do you think you will get a NOI Gold Medal and make Chinese team?

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    3 years ago, hide # ^ |
     
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    It's really tough. making it into the Chinese national team is like a dream which i don't think actually will happen, but worth the efforts to try to go for it

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      3 years ago, hide # ^ |
       
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      You got it! Since you have many years left, I think you have a really good chance! There is one guy from my school that is also from Jiangsu Province, he came here about two years ago, he might also be from your school as well.

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You are 2 months younger than me...and have a rating 800 higher than me.

We're both from Jiangsu. What's the difference?

I wonder what do you do to rest between trainings.

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god

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What are your current goals for the future?

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congratulations!!!

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However, you didn't even enter the NOI (one of the top CP contests in China) while participants the same age or even smaller than you get gold/silver medal in this contest, like strapple got gold medal, wsc2008qwq and jiangbowen got silver medal.

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    3 years ago, hide # ^ |
     
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    yeah because they're way stronger than me of course

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      3 years ago, hide # ^ |
       
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      What are the differences between CF and NOI that affect yours and other people's performance?

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        3 years ago, hide # ^ |
         
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        in china oi contests don't have real-time judging systems and you can easily lose lots of points in a simple task if not careful enough

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          3 years ago, hide # ^ |
           
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          At the same time, Chinese OI contests last much longer (for NOI, 5 hours), there are more partial scores without subtask, and the problems are not that adhoc.

          Anyway, wish you good luck and hope you can reach Gold Medal in NOI2024.

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          7 months ago, hide # ^ |
           
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          Kinda late to this(I was just searching through blogs for some reason) but trust me, not having real time judging is way better than having a real-time judge that randomly stops judging, you can at least have your strategy based on not having a judge in your system...

          Last years Turkish NOI had the judge not working for the last 2 and a half hours of the first day, and then they decided that we submit codes without a judge and they test later. It was a horrible day, a lot of people(including me) underperformed a lot. I didn't have any experience wihtout real-time judging so I scored like 40th in the first day, and scored 5th on the second day... so, knowing that you don't know a judge in advance is probably better.

          Anyways, respect to everyone doing CP in environments like China where you can be an LGM and still fail to join the team... I probably wouldn't even start CP in that kind of an environment

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Teach me.

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which was the last movie you watched?

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%%%Kevin

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Hi. Do you have a personal life?

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What is your next goal? :D

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What's your favourite prime?

What's your favourite prime in $$$[10^5,10^6)$$$, $$$[10^6,10^7)$$$, $$$[10^7,10^8)$$$, $$$[10^8,10^9)$$$, $$$[10^9,10^{10})$$$, respectively?

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Do you play chess? If you do, then how much is your ELO?

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I am also 14 years old, but you understand the difference between us, I am a newbie and you are a legendary grandmaster.

P.S. how did you become so smart?

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    3 years ago, hide # ^ |
     
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    not smart but you can get better by effective training or stuff

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      3 years ago, hide # ^ |
       
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      how did you trained at school times and in holiday times , I cant do intense training on my own but maybe hearing your training program might help me and lots of people note : I am not looking for a strict program and most people dont use one , just explain what did you do for the sake of cp , which resources you used and how intense you practiced.

      also do you think your training program is effective , and what do you think most people are doing weong when it comes to practicing above the level of 1600+

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Can you teach me to learn OI?

i'm 14 yo too,but I don't even have a chance to go to NOI or reach lgm.

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What is your dream life?

What are your long term ambitions.

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I'm suck at solving codeforce problems in contests (mostly because I am not familiar to the speed-wins strategy). But on the other hand, I can solve problems which are more likely to be in my national (province) team selection. Should I temporarily stop doing codeforce and only focusing on solving OI style probs? And when should I comeback to participate in contests as my previlige goal is to get into the national team.

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    3 years ago, hide # ^ |
     
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    you don't need to speed-win to get practised and positive delta in codeforces actually. try solve more problems in contests or upsolve them if you don't have enough time

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any sports?

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Hi!

Q1
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Your achievement at 14 is truly impressive!

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I'm impressed with your progress! Tell me what your typical average day is like. When do you wake up? How much time do you spend at school? For programming lessons? Is there time for sports and friends? Books, movies?

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    I go to school regularly just like all my classmates in the middle school but fortunately my schoolday ends really early at like 4pm or so. And usually i start training after dinner and until ten thirty

    Now in the vacation I practice all day long while resting for maybe half an hour if i feel like relaxing. and interestingly i sleep really late at midnight or even later, and i got up at 10 or so in vacations.

    I always have a day off with my friends occasionally for some sports or just for fun. didn't really got time for books or movies actually :(

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What will you do if you lose motivation? What advice you will give for a CP beginner, like how/where to practice and stuff?

btw congrats on LGM :orz:

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    just sleep if you lose motivation or randomly choose a relatively easier problem from the set to solve

    i really suggest beginners to find a teacher/friend/... to help you and be with you through your CP journey as they can give you really useful suggestions and company

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Any advice for me how to practice?

Brief introduction of myself: Chinese, 14yo.

What did I do in my life? Entering depression mode...

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Are you the youngest LGM?

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Wow. Orz Kevin.

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Your progress is really fascinating !

How much do you practice a day on average ?

What do you think is the thing that most contributed in you reaching this place ?

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    3 years ago, hide # ^ |
     
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    I actually can't accurately estimate how long i spent on relaxing a day between practicing lol

    for q2, i think it's the interest

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How to reach LGM?

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What do you think was the most important thing for your improvement in CP?

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What's your learning strategy? Do you do topic-specific learning (focusing on one technique at once), or a more general approach? Also, do you have the "CP perfectionist" mentality (you never want to look at the solution)?

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How is it possible for a 14yo to be a LGM?

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Wooooow,I'm shocking at 14 years old legendary.how much hours do you study?Do you have teacher or used to have?

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why your username is so reek!Nun Heh Heh Aaaaaaaaaaa!(p.s 114514 and reek is a chinese and japanese meme which also appears here)

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When did you start your CP journey? To what extent do you think genetics matter to the CP performance?

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    4 years ago. And I don't think IQ or genetics are that important, if you got the hard work everything will still be fine without a high IQ

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Dang this is really impressive! Orz!

I've got one question:

What do you recommend to do in order to not get distracted when practicing? This is a problem that I'm struggling with rn unfortunately.

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    3 years ago, hide # ^ |
     
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    change the proxy settings to make it impossible to connect to websites like youtube or so lol
    that's what i tried before and it turns out useful

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Where can I get good at math related to CP ?

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Wow!

I was not even aware of CP when I was 14, you're so intelligent!

Wish to see you in top 10 rated people in near future ;)

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Do you think you are talented compared to others?

What kind of difficulty do you think I should train?

Do you think it's a good idea to think one problem for a long time (e.g. 1 or 2 hours) before checking the editorial?

Do you think it's talent reasons if someone trains a lot effectively but still fail to reach a high rating?

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What are your thoughts on the quantity of problems to the quality and difficulty? I see that you've solved around 1000 problems, did you solve problems from other platforms too?

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    you should choose the right difficulty like just right above your ability range to solve, and of course i solve problems from atcoder luogu cses and stuff

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I wonder, did you loose IOI in your past life and then reincarnate to take revenge ?

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congratulations for being LGM at 14!

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At what age you have started cp?

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Congratulate!

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How did you reach LGM at such a young age? Have you been practicing coding since, like 8?

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Can I also become LGM at 14? I am 16 rn but is that a barrier?

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Did praying Pangu help you becoming LGM ?

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May be Some tips for noob coders like me?

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What wasn't enough for you to get in NOI? Thanks for the answer beforehand :)

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Do you have competitive math backgrounds? If so, what?

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Congratulations on LGM!

Like i have asked on other AMAs, what is your favorite pokemon? :3

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What about coming in Top 10?

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Do you exercise regularly?

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I'm 13, does this mean by 14 I'll reach lgm just like you?

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What do you think of Karry5307?

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Do you play any sports such as table tennis or something? Any favorite video game?

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Which books do you suggest reading to reach LGM and which CP websites do you like most ?

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Do you listen to twice to boost your performance while solving problems ? Or do you listen to JPOP

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In China, you can go to IOI at most one time, right? Do you want to go to IOI as soon as possible, or you will wait a few more years to me "sure" to win IOI?

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Is China's selection for the IOI harder than the IOI itself?

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What is your aim in life?

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Bro u shud b smart then most right, Do u think u shud b allowed to watch 18+ content?

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very good OIer love from HBA.

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    3 years ago, hide # ^ |
     
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    I last heard about u is when EasonTao was talking about '地瓜' stuff & u replied with '你结扎啦'

    about 1 years ago,,, lol

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Hey Kevin114514 ,Congrats on LGM at such a young Age. Guide me brother I want to be CM and about practice I have practiced over 1500 Qs as well as around 100+ Contests Experience.. Any Suggestions from your side???

2nd Q : What is significance of 114514 in your name?

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Can we meet at NOI one day?

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if you face algorithm to start and it has a lot of information and a long study (dp) how do you deal with this?

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i'm literally 7 days older than Kevin. Losing my confidence fr

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Are your friends in school also interested in CP? And if so do you have any friends who are better than you, or anybody that you might look up to in specific?

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how to solve tough problems even after learning so many concepts i feel that i am useless. ideas really don't hit into my mind. picking the questions from range 1200 -1300 make me depressed . can you please tell what you do when you are unable to solve a problem and how much time you spent on a problem.

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Have you read TAOCP? (if yes, which ones?)

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I'm 22 and Indian . I regret not knowing about CP before . Congratulations on reaching LGM at such a young age . I'll also work really hard to atleast reach orange . Did you use Codemao classes to train ? What is the name of your training institute ? Do they provide online training ? I want to really really really get better at this and because I'm on my own. It's not helping at all . Any mentors , please ?

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I hope my son became LGM at 14yo too, not gray :)

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What do you do when you can't understand the sol of a problem or you just don't want to code the sol because it's very long?

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    if i can't understand it, i would probably just put it aside and wait for the right moment when i get the point

    for the problems with long codes, imo you needn't code all of them but you should do one occasionally

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Have you ever read wuxia or xianxia?

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What data structures and algorithms do you know?

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Can you beat SkyWave in JSOI2024?

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Cool, another young talented LGM! If you cannot solve a problem, how long do you think before checking the tutorial?

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    If that's the type of problems i don't master well I will check the tutorial and learn the solution before thinking for really long, but for most problems I suggest a day or so

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Any discord servers for CP , please? Anything will do , I'm a loner and I need to find someone to do CP with

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Congratulations to you. I always don't get the right ideas during exams. Do you have any good training suggestions? Or are there any good ways to think?

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How did you achieve such a sharp jump in progress during Jan-April 2020?

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Congratulations on becoming the new LGM! I am 14 too, but I am still an Expert :)

What is your favorite algorithm and data structure?

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So can you give a link in oier.baoshuo.dev?

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Have you taken an IQ test? if yes can you tell me your score? if not, can you take this one? (keep in mind that online tests reliability is questionable)

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    Just did it on the site you linked.
    unfortunately i haven't got enough time to do the whole test so i choose the one i think fits best for some problems i don't actually know the answers to.
    Got 142 as a result, what level is that

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      Hello, you're really impressive! I just took a test and got only 112. No wonder you are LGM.

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Teach me how to set a problem and be a LGM quickly?

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can you please review my profile? and can give some advice?

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How to master dp and graphs....pls tell some resources for both as these are the most important topics

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How to quickly debug big data structure like fhq treap? I spend hours debugging it.

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https://oier.baoshuo.dev/oier/82575 is that you? You can get such a high score in Senior Group when you are in Grade 8! I can never do it.

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First of all, I wanna thank you for doing this! I am sure everyone here in this thread appreciates it!

What do you think about the solved problem quantity vs quality? Is it possible to solve less but harder problems to get more efficiency in terms of rating improvement in Codeforces?

Afaik, BenQ spends around 30 mins of focused attempt to solve a problem and then take a look on the editorials while other reds suggest to try to attack the problem until you solve it. What's your suggested strategy for Div-2s like me?

Some people say that you don't have to know more than a binary search to reach 1600. Do you agree with this statement?

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    1. quality is important
    2. same as benq i suppose, cause in div2 problems you often can't solve because you haven't seen the type of problem/trick/... and it's good to take a look at the editorial. but be aware when you find yourself failing to solve multiple problems of the same type again and again
    3. maybe binary search and dp are enough, or maybe dp is not necessary
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Did you participarted in National-Olympic-in-Informations?

Did you get AU ,AG or CU?

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3 years ago, hide # |
 
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Is that you?

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3 years ago, hide # |
 
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I see lots of people solve a huge numbers of problems but they are still weak. what is the reason behind that ? and for newbie who practice greedy should I solve all cses searching and sorting problem or its too hard and useless for me.

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3 years ago, hide # |
 
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NFLS wins again:( Not gonna find another OIer so good universally...

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3 years ago, hide # |
 
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you wear specs ?

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3 years ago, hide # |
 
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how much money do u make from cf contests

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2 years ago, hide # |
 
Vote: I like it +56 Vote: I do not like it

Do you know how to check whether a polygon is convex?

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    2 years ago, hide # ^ |
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    If you don't understand the cross product, you can skip this part.

    The correct method is as follows:

    To determine whether a polygon is convex, follow these steps:

    1. Compute the Cross Product:
    • For each set of three consecutive vertices (A), (B), and (C) of the polygon (with wrapping, so after the last vertex, you consider the first one again), compute the z-component of the cross product of the vectors (\vec{AB}) and (\vec{BC}).
    • This is equivalent to computing: [ (B_x — A_x) * (C_y — B_y) — (B_y — A_y) * (C_x — B_x) ] where (A_x), (A_y), (B_x), (B_y), (C_x), and (C_y) are the x and y coordinates of points (A), (B), and (C) respectively.
    • This value will be positive if (C) is to the left of the line (AB) (when walking from (A) to (B)), negative if (C) is to the right, and zero if they are collinear.
    1. Check the Sign:
    • For a polygon to be convex, all these cross products must either be all non-positive or all non-negative.
    • If you find a mix of signs (some positive and some negative), then the polygon is concave.
    1. Special Case for Collinearity:
    • If the cross product is zero for all sets of three consecutive vertices, then the vertices are collinear, and you don't have a polygon in the typical sense.

    By iterating through all the consecutive sets of three vertices and checking the sign of the cross product, you can effectively determine the convexity of the polygon. If all signs are consistent (either all non-negative or all non-positive), the polygon is convex. Otherwise, it's concave.

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    2 years ago, hide # ^ |
     
    Vote: I like it +16 Vote: I do not like it

    great, love you baobao

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2 years ago, hide # |
 
Vote: I like it +24 Vote: I do not like it

Do you know how to check whether a polygon is convex?

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2 years ago, hide # |
 
Vote: I like it +11 Vote: I do not like it

Do you know how to check whether a polygon is convex?

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2 years ago, hide # |
 
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What is the meaning of life?

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2 years ago, hide # |
 
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I like solving problems, but I also like many other things in life. I spend a lot of time doing other things instead of practicing. Maybe a person's potential is limited mainly by how much they enjoy problem-solving. Is there anything you enjoy more?

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23 months ago, hide # |
 
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Very hard contest.Kevin114514 got 115.

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17 months ago, hide # |
 
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how do chinese guys comes to know about imo and ioi in such a younger age

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    4 months ago, hide # ^ |
     
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    Because good performance in provincial/national Olympiads (math, physics, chemistry, biology, informatics) helps you get into a nice university (probably high schools too). So parents want their child to start early and get an edge over others to get the opportunity.

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10 months ago, hide # |
 
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I want a peek into your mindset. Do you believe it was intelligence or hard work that brought you to this point? And how much of a role do you think your environment (family life, finances, and so on) played?

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4 months ago, hide # |
 
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I'm 14 years old right now, and I'm simply a Specialist(I started like 2 years ago). How did you train and grow to become an LGM in 4 years?

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4 months ago, hide # |
 
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my contribution is in negative. Help me reach 0 contribution. Join the cause now and upvote this comment.

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4 months ago, hide # |
 
Vote: I like it +34 Vote: I do not like it

How did you get top1 in Codeforces but only top10 in CTT(China Team Training)?