Me and my friends were working for upcoming ICPC regional. We got stuck at these two problems.

1-(This one is solved in comment sectiom) You are given an array with n elements, you can increase one element's value by one with one cost. Your goal is to make xor of all elements 0 with minimum cost. n <= 1000, a_i <= 10⁹

Here is the link for the problem: http://algotester.com/en/ArchiveProblem/Display/40442

2-You will be given n intervals like [l_i, r_i]. You have to divide these intervals into two subsets A and B such that every interval belongs to exactly one subset and the intersection of A and B maximized and print this subset. The intersection of two sets of intervals is sum of every pair of intervals' (one from A, one from B) intersection length. n <= 100000, 0 <= l_i <= r_i <= 10⁹

Link to this problem: http://algotester.com/en/ArchiveProblem/Display/40384

Thank you for your help (:

Hello Codeforces community,

I would like to invite you to join HackerRank's 101 Hack 55 which starts at 1500 UTC, July 2, 2018.

There will be five tasks and three hours for you to solve them. The contest will be rated and the top ten contestants will receive HackerRank T-shirts!

The problems are prepared by me, muratt. kevinsogo tested the problems and he found them to be interesting. I hope you'll enjoy the problems as much as he did!

Happy Coding!

Hello,

We are an independent non-profit entity with the support of Bev.Foundation and we provide a neutral umbrella for all Turkish hackers.

We are organizing free summer camp between June 28- July 7. Kevin Charles Atienza (kevinsogo) will be with us to guide the students about algorithms, solutions and algorithmic thinking.

The camp is for 100 university students from Turkish universities. We want to invite (travel to İstanbul, accommodation, and food provided) teams for our expert track. Applicants should be currently enrolled in a university.

You can find more details about the camp here: https://inzva.com/algorithmic-competition-summer-camp

Check our ICPC World Finals 2018 video: https://www.youtube.com/watch?v=b6xcEz8zM_0 

For questions feel free to email to [email protected]

I'm glad to invite you all to participate in 101 Hack 39! The contest will start today at 16.30 UTC, July 12.

All problems are prepared by me. It will be my first HackerRank round so far. Also you may want to check my Codeforces round which held very lately Codeforces Round 352 (Div. 1) or Codeforces Round 352 (Div. 2).

There will be five tasks and two hours for you to solve them. Contest will be rated and top-10 contestants on the leaderboard will receive amazing HackerRank T-shirts!

I want to thank wanbo and kalimm for testing problems and for their great advices. It was awesome to work with them.

I hope you will like the problemset. I tried my best to prepare interesting problems, so I strongly recommend you all to participate. Please read all of the problem statements during contest, because some problems may have subtasks and you don't need to find best solution to get points. Also some of the problems may be little harder than usual.

Editorials will be published right after the contest.

Scoring will be 20-40-70-80-100

UPD: Contest has ended! Congratulations to winners! Editorials for every problem are available now.

1.mmaxio

2.anta

3.TeaPot

4.I_love_Tanya_Romanova

5.sugim48

6.kostya_by

7.geniucos

8.bicsi

9.vintage_Vlad_Makeev

10.Arterm

672A - Летняя школа

This one is a simple brute force problem, we will construct our array. Adding numbers between 1 and 370 will be enough. After construction we just have to print n-th element of array.

672B - Разнообразие - это хорошо

We observe that in a good string all letters must be different, because all substrings in size 1 must be different. So if size of string is greater than 26 then answer must be  - 1 since we only have 26 different letters.

Otherwise, Let's suppose we have k different letters in string sized n, in our string k elements must be stay as before, all others must be changed. So will be (n — k). Here is the code.

671A - Мусор на переработку

Let's solve the problem when Adil and Bera in the same coordinate with bin. Then answer will be , let's say T to this value.

Hello Codeforces!

I am glad to invite you all to participate in regular Codeforces Round #352 that will take place on 11 May, 19:35 MSK. This will be my first round, so I hope that it will be interesting for you guys. There will be 5 problems for each division, and contest will last 2 hours.

Round wouldn't take place without the help of GlebsHP, I am very thankful for his great help. I also want to thank to Zlobober, winger, AlexFetisov, ikbal and ykaya for testing problems, to hasanb for inspiring me in a problem. I got great help and wise advices from all of them so this is their round too as much as mine. Of course I want to thank Mike and all others who puts his effort into Codeforces and Polygon systems. I don't know what we would do without this great platform.

UPD1: Score distribution:

Div. 2: 500-1000-1500-2000-2500

Div. 1: 500-1000-1500-2000-3000

UPD2: I will post editorial as soon as possible, thank you for your patience. Congratulations to winners!

Div.1 winners:

1-subscriber

2-W4yneb0t

3-jcvb

4-Merkurev

5--XraY-

Div.2 winners:

1-the_arr_of_war

2-Shavkat_Aminov

3-Lightning34

4-I_Love_Ginger

5-tjandra

UPD3: Editorial is now available.