Thanks, I already posted it there LinkedIn Post

I have no problem, but I think it is better to keep cf and other online judges as they are, specialized and focus on enriching the CP community with exclusive problems and challenges and social network a place that connects everyone where they enjoy their time, share memes, socializing and also helps everyone to improve but in a different way than training.

no, I mean after the round ends, they can view the tutorials they couldn't solve during the live round. like during the live round they got WA verdict in problem C, after the round the can find the solution of it in their newsfeed

I know how much effort these guys put into training as much as I know they would do a great job there.

With my best wishes to every member in this team.

The anime deals with many great things and one of the things the story focus on is the importance of the training in a realistic way.

This realistic appeared in the Might Guy fight with Madara and the impressive performance that he showed but he couldn't win the fight.

Naruto

The anime stress the relation between the development of the characters and the efforts that they put in the training, what ever how far do these characters talented or not.

I claim that this round will be one of the best Div 2 rounds ever.

Thanks

Thanks

Thanks

Thanks

Thanks Ahmed

Thanks

Thanks

I made a video for up solving the round ( div2 without F ) with Arabic commentary here

Don't talk about ACPC20 like any other ICPC contest

I think we have the same approach with different implementation way

$$$gcd(x,y)$$$ equals to the multiplication of all the common factors between $$$x$$$ and $$$y$$$.

$$$gcdHBD(x,y)$$$ equals to the multiplication of the first $$$k$$$ factors of $$$x$$$ and the last $$$k$$$ factors of $$$y$$$ .

so $$$gcd(x,y)$$$ = $$$gcdHBD(x,y)$$$ iff the first $$$k$$$ factors of $$$x$$$ are common factors in $$$y$$$ and the last $$$k$$$ factors of $$$y$$$ are common in $$$x$$$.

so $$$x$$$ and $$$y$$$ should have at least $$$2k$$$ factors.

now let's get the maximum value of $$$k$$$ in the worst case: $$$gcd(x,y)$$$ <= $$$n$$$ and $$$n \lt =10^5$$$ in the worst case all the factors will be equals to $$$2$$$. so $$$k$$$ <= $$$log2(10^5)/2$$$ , $$$k$$$ <= $$$8$$$.

so if $$$k$$$ > $$$8$$$ the answer is $$$0$$$.

so what to do if $$$k$$$ <= $$$8$$$ ?

for each integer $$$x$$$ $$$[1,n]$$$
1- get it's factors.

2- remove the first $$$k$$$ factors from it ( that are common in $$$x$$$ and $$$y$$$ )

3- backtrack in these remaning factors to get the last $$$k$$$ factors ( that are common in $$$x$$$ and $$$y$$$ ).

4- make another backtrack to get another factors that are not in $$$x$$$ so can't affect the $$$gcd$$$ ( on primes from $$$2$$$ to $$$r$$$ where $$$r$$$ is the lowest factor in $$$y$$$ )

code : https://ideone.com/61h70N

It's a joyful thing to me to see Arabic round again. Hope our contribution in problem solving community keep it's progress and see more Arabic rounds in the future.

I am realy intersted to praticipate in your round ,thank you guys.

it is great to see how does CF is growing every day , great thanks for this great community who are working to make CF is a complete platform for any compatitive programmer in any learning phase

there is no logic in making the difference between some problem's score and some other harder problem's score too little just to make F+G=H

I was thinking about skipping this round as I have an exam the day after this round but your comment made me ignore the idea :D

A participant

I really had enjoyed testing it ,and highly recommend it for every one

Auto comment: topic has been updated by Uzumaki_Narutoo (previous revision, new revision, compare).

I added it to the blog ... sorry for that :D

Revive

because you merged between printf and cout with fast i/o I mean these lines ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

don't let the downvotes frustrate you , It is all about a long journey of hard working . wish you the best ❤️

being in top 500 in combined round means his real rate should be higher

Waiting for interesting problems as expected from you

the internet connection is not stable now a days here in Egypt

Me too

my contribution rank became 29790 from 29820 :DD

he didn't mean that for sure ,by the way I really had interested in dancing with the African group

I agree but I am sure that he was just making fun with them

That's how we make fun with each other here in Egypt .. I think it is not Racism ,it is just cultural difference that leads to miss understanding

Team name : Counter att-AC-k ,from : FCIS Ain Shams University ,Egypt Uzumaki_Narutoo HadyMosaad Mark_Louba

seems he is going to do so

It hadn't updated yet

why not giving it to someone who can care instead?

If you filled the first row cells and first colm cells you will find that there is only one way to fill the remaining cells

It was the best round I had participated in from a long time

string is good if all it's characters are in palindrome substring of this string

I also got it I'm Egyptian

I think the problem D statement was not clear ... there is no thing refer the the permutation is of indexes not permutation of elements it self ( it different in handle the same permutations )

You are right

Any why ,he still just a kid but he make a great performance and we should encourage him note : متشكرين يرجولة means thanks in Arabic :D

more than 1 hour and half trying to understand C , LOL :D

in problem C , I see the we should use a of the first plant first then for all remaining plants should use b first the a as landing will be before flying and the order is very important as the weight of fuel will update after each fly or land I mean some thing like this

bool can(double fuel){
    double temp=(m+fuel)/a[0];
    fuel-=temp ;
    for(int i=1;i<n;++i){
        temp=(m+fuel)/b[i];
        fuel-=temp ;
        temp=(m+fuel)/a[i];
        fuel-=temp ;
    }
    temp=(m+fuel)/b[0];
    return (f-temp)>=0 ;
}

but I found some solutions had got AC and they don't care about the order of flying and landing ,How ? thanks in advance ^_^ UPD: I got confused in reading that code ,there is no problem xDD

also I think rounds like this is very very unfair for the participates and don't show their skills

It is unbelievable to see that there are 3 problems more the 3000 one had solved it and another 2 ,one of them 20 but the other is 8 (just passed the pretest)

Am I in hackforces round? -_-

It was one of the most interesting contests that I had participate before thanks for this great contest ^_^

It was my first time to get tagged in official codeforces round .. Awesome ^_^

B and C in div2 have the same score ,Will they have the same difficulty ?

Good Luck , wish less implementation problems :D

_HossamYehia_ XD

I don't know why your comment get down voted ?

Good luck

It is very cool that make a big challenge in hacking

and if it is , they should make a note for that , not an announcement after more than 1 hour from the beginning of the contest !!

Of curse it is very good to know but I think in rated contests you should avoid the differences like this

but there are a lot of languages like java that has big integers so , I am talking about the judge should avoid the differences between the languages

It is very unfair for the beginners who can't write else c++ !! what is the purpose of problem else to impossible the beginners for not trying for solve !! I think there are a lot of us who are very very angry and ask you to edit the test cases to not exceed 10^18 .

the answer in problem d can exceed 10^18 It is very unfair for c++ coders

It's very nice to see "Kotlin" in "ICPC" , but no one in my region will care , as it is not allowed to use in .