I've recently started solving problems on AtCoder and noticed that the quality of problems is exceptional. Obviously Codeforces also offers great problems, AtCoder's seem to be on another level. Does anyone know why this might be? One possible reason could be that AtCoder hosts contests less frequently than Codeforces, allowing them to maintain a higher standard for problem quality .
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I think less no words in Problem Statement of AtCoder makes it diff from other CP Websites
That's not what I meant. Ofc the problem statements are short. But I meant, the "idea" to solve the problems are insanely good and imaginative. They use relatively simple techniques in very clever ways.
They are "so good" if you enjoy dumb math tricks. If you want codeforces to "maintain a higher standard" like this, just only accept rounds where all problems rely on invariants or variable substitutions, with statements and setups that have even less to do with the a real process you'd want to solve than on other websites.
I think AtCoder helps you get better in some important algos like Bs or DSU or the dumb math tricks as you said.
Controversial statement
Ask strong contestants (IGM or LGM), and most of them would agree, search for old blogs to see for yourself.
See for yourself
Agree on what?
Most high rated people disagree with the guy. That is why the current meta is what it is
that's why we need more Chinese style rounds
the first rounds would obviously be downvoted to hell but then the meta will gradually change
When have CP problems been about resembling "a real process"
It's not like people made up algorithm ideas for no reason throughout history, and there are cp problems that reflect this. However, higher rated cp people more and more actively choose to make up nonsense instead of ideas that have some resemblance to could be useful, and like to recycle the same few Olympiad combinatorics math tricks in increasingly contrived setups.
I think good problems are usually made thinking about what is real problem you want to solve and idealizing until solveable. But many just like to mash together random ideas and ask is this setup solveable (and when they come from the same set of math constructions they usually end up recycling the same line of insights), or force a problem onto a solution while trying to hide the inspiration through contrived setup.
By your standards almost all CP problems are bad. For some topics all problems would be considered bad. It is goal of problemsetters to improve the problem solving abilities of other people. Number theory was useless for most of human history until modern cryptography became important, which was invented through generations of people coming up with new "useless" theory.
Also I don't understand the "recycling the same line of insights" part. There are examples of those, but you can't tell me that these kind of problems occur all or even most of the time on Atcoder.
I think there isn't much problem rely on invariant or variable substitution in my experience (at least ~ orange, not sure about red~ but probably not much still). And I feel most of the problems from ARC and old AGC can be solved by just proper reasoning and basic combinatoric skill rather than you said "weird math trick".
AtCoder is just better than Codeforces.
i never gave atcoder a real chance only tried afew ABC problems and 1 ARC and left is it really that good ?
The problems are straight-forward and are written formally, so you skip the part where you "translate" the statement. I think that's the most significant reason why they are so good.
They steal from codeforces
Referencing Zhtluo's blog, I think Atcoder is really good because it combines problems of all three types — there are some niche observation based problems, some problems requiring knowledge of particular data structures and some requiring plain heavy implementation. Codeforces is more biased towards observation but Atcoder maintains a fine balance among all "aspects" of problem solving. (This might not be true for Div1Fs and AGCs though, I have never tried those).
Edit: Whoops, I guess that's true for ABCs only.
This is.....totally wrong.....
Atcoder has predominantly observation based problems while CF has more implemention/data structure (still a lot of observations problems in CF too, but definitely less than Atcoder)
It is well known that maroonrk likes problems a certain way and he regards thinking >>> ds as a crucial aspect of any good problem
I agree with him, and it is the reason Atcoder is so good.
(This is assuming you dont count abcs as atcoder)
these new ABCs are total bs, imo ABCs where also "atcoder", in the 100-200 contest ids
I think since their problems are very concise. But sometimes it is overdone and you must decipher their use of notation to figure out something that could be more clearly described using language.
the same reason anime is better than cartoons
oh yes, its JAPAN
Aoki and Takahashi instead of Alice and Bob
another sad case of affirmative action taking jobs
Actually ABC problems are much worse than CF Div3 problems, but ARC problems are really great.
I thought ABCs were good as someone suggested me if you wanna improve in fast solving then solve ABCs of atcoder they will improve your fast solving. But I haven't solved much ABCs but they are generally easier than div2 can't compare with div 3 though bcz I feel sometimes C of ABCs are pretty good compared to div3 ones
Div2>ABC>Div3