### Arpa's blog

By Arpa, history, 6 months ago, ,

Hello!

Welcome to June Easy '19, from our easy and educational contest series. It's a 3-hour competition with six algorithmic tasks. We are going to hold it on Sunday at 16:00 GMT. Check contest page for more details.

I helped Danylo Danylo99 Mocherniuk, Mohammad-Mahdi Kerpoo Taheri, and, Dishant Dishant_18 Trivedi setting this round. AmirHossein amsen Pashaee and I are testers of the contest. As usual, here are the prizes for the top three contestants:

• $75 Amazon gift card •$50 Amazon gift card

Note that prizes and T-shirts are given to top participants with ratings < 1600 (beginners).

GL & HF.

Let's discuss the problems after the contest!

P. S. Sorry for problems occurred. Now everything fixed.

• +30

 » 6 months ago, # |   +27 Why there is no leaderboard? Where can I ask clarification?
 » 6 months ago, # |   +3 Can anyone just clarify the problem "Minimum Cost"? The statement is not doing much justice. Just need clarification nothing else.
•  » » 6 months ago, # ^ |   0 You can go from i to p[i] with cost 0.
•  » » 6 months ago, # ^ |   0 Sorry, refresh the page.
•  » » » 6 months ago, # ^ |   +4 Constraint on N is showing the Constraint of T..
 » 6 months ago, # |   0 In prob 5, why does sample contain 8 rows while in the input section described 6 rows? Also, it states to output answer with exactly 5 digits while sample is with 6 digits after dot.
•  » » 6 months ago, # ^ |   0 Sorry, please refresh the page.
•  » » » 6 months ago, # ^ |   +10 I refreshed the page and all my submissions disappeared. Should I try to solve problems or give up? :)
•  » » » » 6 months ago, # ^ |   0 I don't know about the back-end. I'll ask them.
•  » » » » 6 months ago, # ^ |   0 Fixed.
 » 6 months ago, # |   0 Please, add limitations for N in problem 4.
•  » » 6 months ago, # ^ |   0 Fixed.
 » 6 months ago, # |   -18 Not easy contest. Please next time only give name June contest
•  » » 6 months ago, # ^ |   +4 In contrast with other contests, it's an easy one.
•  » » » 6 months ago, # ^ |   0 Strongly agree :)
 » 6 months ago, # |   0 Why there are no explanations in the editorials?
•  » » 6 months ago, # ^ |   0 They'll be posted today.
•  » » » 6 months ago, # ^ |   0 Kindly Post the editorial.
 » 6 months ago, # |   0 Can someone explain the use of XOR in Mosaics and holes. Or any other method to solve.
•  » » 6 months ago, # ^ |   0 Take update array of size M and vector > v[N]. By traversing for each index starting from top left, take current position as i,j.case 1. if value at this position is 0 and no. of total updates is even at this position so, it means value is still zero here. To change it,we will flip K*K matrix having top left at this position. Now, I have taken update array I will update this position with +1 and upd[j+k] with -1. And v[i+k].push_back({j,j+k}). This is because when I will be at (i+k)th row, I no longer need these updates.So at that time do this upd[j]--; and upd[j+k]++;case 2. if value at (i,j) is 1 and no. of updates at this position is odd, It means now value is zero. To change it, we will have to flip k*k matrix with top left at this position and do same as in step 1.In both cases, If it is unable to flip K*K matrix with top left at that position. I mean if((j+k-1)>=m || (i+k-1)>=n) then answer is -1.