I have been doing CP for more than 1 year. I have observed there are so many people who reach Expert, Candidate Master without putting much efforts in very less time.
People like me have to solve like 100 problems of a certain difficulty to become comfortable for that difficulty whereas they don't practice many questions and they are still able to solve them.
Chinese Coders, Many IITians are the people with whom I observed this phenomenon the most.
People can have competitive programming experience before creating a codeforces account. I know that this is the case with many Chinese users who achieve a high rating in their first few contests.
no, they aren't.
to elaborate, you're underestimating factors outside Codeforces. they may have backgrounds in problem solving outside Codeforces, such as local communities, other online judges (this was true in my case), etc. most people who got so far in CP had engaged in CP for a significant portion of their lives. getting good at something without effort is almost (if not at all cases) impossible. this is all I can tell you.
You can get better at CP without doing CP — math contests and the olympiad math thought process provide a huge boost to any CP newcomer.
that counts as effort too
Yeah, not disputing that — I'm just tired of people saying that everyone who started CP quickly is either an alt or have used other online judges. There are more possibilities :P
true, people have many backgrounds. other OJs was just one example :)
CP consists of problem solving then implementation. The problem solving part can be read as math ability, which I think is half innate and half trained. It's hard to be trained in math and it really takes time (same holds for the implementation part but the required knowledge and time would be much higher in math). Anyways, if you are not trained in math already, the probability to improve quickly is very small (basically only possible when you are innately good at math). You would have to spend time in math/problem solving (through cp or in any other form as well) nearly as much as other people already spent.
1) Lots of people practice on other online judges (e.g. DMOJ, oj.uz) and take CF contests on the side
2) Quality over quantity
it's enough to learn math in middle school
genetics
You need to travel a lot.
don't copmare urself by other too much , it is double-edged sword , it enough to know ur skill is improve , and compare urself today by urself yesterday is more effective and health for u .
Some of these people have been putting in efforts in CP in ways that aren't visible to you. Let's say that they are practicing more on sites like Timus or Codechef or AtCoder or any other site other that CodeForces. Hence, you think that they aren't putting in that much effort, but in reality, they are.
Some others, particularly the Chinese folks, have already done great in other similar fields like mathematics, physics or econometrics etc. So they have skills that are highly transferrable to CP. So, in a way, they too have put in a lot of efforts in CP, albeit indirectly.
Stop looking for excuses and grind problems.
Best of causality.
Performance Enhancement Drugs.