C is beautiful nice contest

Last point should be first ig.

I hope they don't change it to rated in last mins(April Fool).

I have completed all the steps and have used the following Sublime-build as per g++-13(I have gcc installed).

{
    "shell_cmd": "/opt/homebrew/bin/g++-13 \"$$${file}\" -o \"$$${file_path}/$$${file_base_name}\"", "file_regex": "^(..[^:]*):([0-9]+):?([0-9]+)?:? (.*)$$$",
    "working_dir": "$$${file_path}", "selector": "source.c, source.c++", "variants": [ { "name": "Run", "shell_cmd": "/opt/homebrew/bin/g++-13 -O2 -static -Wno-unused-result -std=c++17 -DONLINEJUDGE \"$$${file}\" -o \"$$${file_path}/$$${file_base_name}\" && \"$$${file_path}/$$${file_base_name}\""
        }
    ]
}

I am getting the following error upon running (the build is succeessful).

Can somebody please help me with this .

When I submit solutions after the contest is over ?

Can somebody explain why my solution is getting TLE'D on test 15 for problem D 242631259

Hi, Can somebody explain why this Code for Problem D gives Runtime Error 241826844.

Can somebody please explain why this Binary search for Problem D1 fails on Test 5 236231559

Excellent analysis. Implementation of the above idea 236158727.

Will the round be delayed if this queue continue ?

in problem D ,Can anybody provide me a idea on how to check within ranges from L to R

practise on certain CM rating and giving virtual contests to improve time in solving upon that maybe helpful for any rating range imo

Lol True !!!

I couldn't understand Problem C can somebody explain me the problem statement !!

Superb explanation !!! Thanks a lot , One thing I would like to know is if the question constraint that you can buy more than a[i] items of ith item would affect the solution in case we buy more items of x so as to more decrease y

Can anyone please provide a solution to problem C Yet Another Card Deck using Binary Indexed Tree

Thanks !! Will try to incorporate the changes within me

You too !!

Can somebody please explain problem B Quadruple ??

I just open this blog from time to time to note your reaction on this very blog !!! Lol

I think 6 is coordinate compression

Join discord server of Errichto, You can challenge anyone registered as a duelist

I tried doing it but didn't work out for me, is there any other way ?? I am using a different network currently

Codeforces is not opening with one of my home networks however I can easily access it on other networks at my home

I also am facing the same problem since yesterday don't know how to solve

Lol, Missed the intended solution on problem A Did it using BIT .

I slightly changed the ordering when the two consecutive elements were considered starting from odd position and got accepted Check this 85213408

Yes sometimes long long can lead a just passing soln to TLE

Can it be solved using two pointers ?? considering the largest even subarray such that the sum of elements at odd position is greater than sum of elements at even position and adding the remaining even sums at both ends ??

Why did their ratings got increased weren't they excluded from the round ??

Work done = Effort x Time taken , Increase your efforts you will automatically gain time :)

The proofs are really elaborate and detailed , It really helped someone like me Thanks :)

What would be the average diffuculty of the contest ?

I tried this code for checking point within the convex hull(the problem that appeared in the last long challenge on Codechef and I kept getting WA ) Now I understand why did it happened :(

amazing...

lol !! I was about to add 10 nanoseconds XD

It would be quite informative if you would cover areas involving Machine Learning , Deep Learning etc

iterating over 0 to bits and for each k taking all possibilities of x would be O(bits * bits * (2^bits)). did you also include the complexity of calculating all submasks of mask for each x ??

Actually i did the same

Me too same story :( feeling really bad

I Wonder how the submissions would have been XD

Same with me bro got -112 worst ever today , intrestingly at the very end of the contest I was trying segtree with binary search to solve A XD

I had done some similar problems recently involving similar ideas and after misinterpreting what "subarray" meant I thought that was the best way to go !!! XD Moreover I just had to edit the code slightly to adjust the problem rather than creating one from scratch

Well I never knew what the definition of "subarray" meant for this contest until the contest ended :(

it gives 5 which a/c to me is correct

Can you Please tell if I misinterpreted the definition of the subarray here , otherwise my soln seems fine 83678283

Edit : I did :(

same with me I tried segtree and BS but kept getting WA over 4 times is some problem with the approach ??

Did somebody please Help why I am getting WA on test 2 of problem A , I used Binary Search and Segment tree 83678283

Edit : Wrong Logic

In test case 1, 3rd subtask we had 2 ones and 2 zeros (101,101,100,100) till 3rd position starting from (1,1) while also we had 2 zeros and 2 ones (101,101,100,100) at 3rd position starting from (n,m) then why the cell at (2,2) was changed to 1, Also in 1st test case 1 subtask this same scenario happened we had one zero and 1 one (10,11) till 2nd postion also we had the same strings from (n,m) till 2nd position then why there were no changes ? Please Correct me if missed something.

for example if the matrix is [[1,0,0] , [1,1,1] , [0,0,1]] the final matrix will be of which form ??

Will our choice at length n-i of string would depend on our choice of i done earlier ?? (Will the value at cell(i,j) change )

I did the same using dp[i][0] for storing number of 0's till i length form (1,1) Similarly dp[i][1] , and kept getting WA on 1st test itself and lost midway :( Did you mean that the last part has to be done for the complete string or till mid of the string

What observation did you make in C ?? after first reading I thought I had to convert all the strings into a palindrome (if they are not obviously),Moreover the test cases created more confusion.I still can't get the question clearly :( My bad

I did it with multi source bfs https://ideone.com/j6Ujgn

Ya !! Infact it seemed that even top sort would pass !!

I did it using dp 82541393

I thought maybe its topological sort but got WA on 5th case :(

Can somebody expalin why this soln to problem C is giving wrong on Test 3 81903363 ?? I did it with binary search

Edit :- Can somebody confirm whether It failed due to precision errors ??

Can you please explain how you got there ?? though I observed a zig-zag matrix of different sizes same sum

Can you share your approach please !!

Can somebody explain how to solve problem C ??

Am I the only one who felt G to be harder than H ??

they will be delayed , i think !!

Yeah !! I too think the same

the length of square will be equal to the longest diagonal in the polygon for which the formula is L / ( 2 * sin( 90(deg) / n ) ) where L is the length of edge of regular polygon and n is the number of vertices You can refer to the proof here

for C2 , the length of square used is equal to the length of the longest diagonal of the polygon

I also did the same and got WA :(

Can Somebody Explain Why this soln to Div -2 C is getting TLED 79963348 ??? The complexity is O(n*n/(log(n)))

Edit : The complexity is not enough to pass

Can somebody explain why this solution to problem E is getting TLED ?? 79579514 it runs I think within 1 sec locally.

For shorter code can't we use PBDS ? , As far as I know they are mainly bound to support these operations ....

Can somebody Please Explain Why I am getting WA on Problem C Submission.

Got your point !! Thanks for the detailed explanation !!

I have actually calculated shortest paths from a-b ,b -c, a-c , if path from len(a-b) = len(a-c) + len(b-c) then c occurs in one of the shortest path from a to b and that path should be considered for optimal soln. otherwise the path from a-b (shortest ) and b-c shortest is considered .Though due to TL the soln might get TLEd but I want to know If the above approach is incorrect!! :)

BTW, Thanks for the reply !!

Can somebody please explain why I am getting WA on E Submission Link

Yeah! BIT is infact developing the same prefix sum , What other approach with BIT is used to solve the problem A/c to you. I am also intrested in the same! :)

You can check this soln by Ashishgup https://codeforces.me/contest/1343/submission/77496545

Can you please Explain your approach to part 2 more clearly !!!

Does anybody knows why the ratings are not credited till now (post this round) ??

Didn't Binary Search would work for Problem C ??

is there a soln to C using Binary search ?

Same with Me I wasn't able to solve A :(

Can somebody Explain why this solution using binary search is wrong (Problem C )?? Submission link

Could you please provide a link of your code on an online ide.this submission link is not opening !!!

Can somebody explain why this solution to problem B gives WA Submission

Can somebody explain why my soln to div 2 D is giving WA ??. Submission Link

My approach is as follows:- My current mex is mx and it is the first element in map with value 0.for all 0<=i<mx value in map is 1. now if yj entered is greater than mx then I am trying to cover up the value just greater than mx whose value in map is 0. Similarly for the case when mx > yj. if mx = yj then finding the next uncovered value in map and updating mx.

Can somebody explain why my solution to problem D( MEX maximizing) is getting TLE'd Submission Link

did somebody solved D using dp ??

Hmm I too think the same

did anybody solved D using DP ??