Among reds and yellows, there is GreenGrape too. :D

I hope the difficulty gap between problems will be proper.

Just love the unstable contests. GreenGrape is here so we can hope for hell of an unstable contest!I mean contest with weak pretests O_o

how many problems will be there?

What is the number of problems? And round duration???

Me in this round.

It's not like I am going to get any GP score, but it seems a bit unreasonable to rank 4 out of 6 contests, especially with the fact that rounds are not announced weeks ahead of the schedule for participants to allocate time slot for the contest.

Nice contest after chinese new year :D Good luck all !

wishing ** Good luck** to everyone who is going to participate. - !NOOB :|

Why am i getting negative contribution without doing anything.

I'm not so sure if this is just me or the case for others too, but I feel like weekends would be more convenient for such rounds, people might be more busy during weekdays. Just an opinion I might be wrong :) Best of luck to those participating in this one!

There used to be a time when questions at the level of C were thought-provoking. Now the contests are like type first 3 fast and sometimes the transition in difficulty is so drastic that as you move from 1 level to another, the difficulty increases manifold. I believe A should be solved by 80%, B should be solved by 60%, C by 20% and D by like 7-8%. And C level questions need to level up.

Well shit. I can't participate again because the time is too early.

How many problems and duration ?

Новый вид раундов, класс. Надеюсь, будет круто :D

Getting One T-shirt can make your motivation level rise to the moons! Best of luck everyone.

Will it be in ACM-rules? Or in CF rules?

Happy Coding guys !

There was(thanks for the correction!) a 'и' in the English post. Now that I learned Russian a little, I do know it means "and" in Russian, but for those who don't know Russian, it's a bit confusing (especially when it's in the problem statement -- which I've encountered long ago, though it was clear from the context that it means "and" ;)

Should we expect an interactive problem?

seem difficult for practicer like me to compete t-shirt...

Feb 7, 2019: Day of emancipation div2 and div3....

Hi everyone!

I got my old PC fixed just in time to do the contest. Excited to do this contest and this is such a nostalgic feeling. Let us enjoy it together, everyone.

Also, 1 like for getting my main PC fixed. or my PC dies. Your upvotes are really needed. Who wants a poor PC that went through such a harsh life of having 50 chrome tabs open every moment to die? Your likes are needed people.

Good luck everyone :D

Happy Rose day to all...

Will the round be sorted by penalties or will points be awarded?

10,000+ registration is now become common for codeforces ):

Are the problems sorted by ther difficulty ?

Wish you good pretests and high rating!

Traditional randomization scripts!

The second script is used to feed random places into the first script. Seed will be the score of the top1 contestant of today's contest, length is the number of people with ranks 31..500 (likely 470) and nwinners is 20.

import requests

contests = [1110]

def is_eligible(contest, party_name, rank, points, problems, last_submission_time):
    return (31 <= rank <= 500)

def get_party_name(party):
    if 'teamName' in party:
        return party['teamName']
    else:
        return party['members'][0]['handle']

class Party:
    def __init__(self, contest, name, rank, points, last_submission_time):
        self.contest = contest
        self.name = name
        self.rank = rank
        self.points = points
        self.last_submission_time = last_submission_time
    
    def __lt__(self, other):
        if self.contest != other.contest:
            return self.contest < other.contest
        if self.rank != other.rank:
            return self.rank < other.rank
        if self.last_submission_time != other.last_submission_time:
            return self.last_submission_time < other.last_submission_time
        return False

eligible = []

for contest in contests:
    rows_to_fetch = 20000
    r = requests.get('https://codeforces.me/api/contest.standings?contestId=%d&from=1&count=%d&showUnofficial=false' % (contest, rows_to_fetch))
    if r.status_code != 200 or r.json()['status'] != 'OK':
        print('Error: failed to fetch results of contest %d.' % contest)
        exit()
    results = r.json()['result']['rows']
    if len(results) == rows_to_fetch:
        print('Error: results are too long in contest %d, increase limit.' % contest)
        exit()
    for row in results:
        party_name = get_party_name(row['party'])
        rank = row['rank']
        points = row['points']
        problems = 0
        last_submission_time = 0
        for problem in row['problemResults']:
            if problem['points'] > 0:
                problems += 1
                last_submission_time = max(last_submission_time, problem['bestSubmissionTimeSeconds'])
        if is_eligible(contest, party_name, rank, points, problems, last_submission_time):
            eligible.append(Party(contest, party_name, rank, points, last_submission_time))

eligible = sorted(eligible)

for i in range(1, len(eligible)):
    if not eligible[i - 1] < eligible[i]:
        print('Error: unable to sort eligible.')
        exit()

for idx, party in enumerate(eligible):
    print('{} {} {} {}'.format(idx + 1, party.contest, party.rank, party.name))

print('Total %d eligible.' % len(eligible))

exit() # comment to see winners

winners = list(map(int, input().split()))
print()
print('Winners are:')
for place in winners:
    print('{} {} {} {}'.format(place, eligible[place - 1].contest, eligible[place - 1].rank, eligible[place - 1].name))

print()
print('| List place | Contest | Rank | Name |')
print('|--|--|--|--|')
for place in winners:
    print('| {} | {} | {} | [user:{}] |'.format(place, eligible[place - 1].contest, eligible[place - 1].rank, eligible[place - 1].name))

#include "testlib.h"
#include <iostream>

using namespace std;

int main(int argc, char *argv[])
{
    if (argc < 4)
    {
        cout << "Command line arguments are: seed length nwinners" << endl;
        return 1;
    }
    int seed = atoi(argv[1]);
    int len = atoi(argv[2]);
    int nwinners = atoi(argv[3]);
    rnd.setSeed(seed);
    
    set<int> winners;
    while (winners.size() < nwinners)
        winners.insert(rnd.next(1, len));
    
    for (auto winner: winners)
        cout << winner << " ";
    cout << endl;
    
    return 0;
}

I think wery0 liked this round wery much. Thanks, problemsetters (especially Mr GreenGrape) for good tasks and fast editorial. Also, I want to say thanks to MikeMirzayanov for great(grape) platforms: Codeforces and Polygon!!!!

How to solve E

Many people used pow function in A which will overflow but those ran fine. Can someone provide a test case on which these overflow solutions will be wrong if any?

A was more interesting than usual. :)

How to solve D?

Very nice problem C!

how to solve B?

Best problem C I've ever seen~

Can someone explain why binary searching for the answer (minimum length) with a greedy function wrong in case of B problem? I kept on getting WA on pretest 7. A hint would suffice.

B was harder than C for me. LOL

how to solve B?no idea :(

Well...I think the pretest of problem A is too weak because I passed the pretest while writing x&1 wrong as x^1...

E is one of the best problem E ever on Codeforces, until I realized that one can fail system test because they forget to check if c[1] ≠ t[1] or c[n] ≠ t[n].

Does this count as cheating? I saw a submission for C where the user created a map of all the possible input a's to the answer. Probably these answers were brute forced earlier and logged?

What is test case 35 in D? Many people including me are failing on that

Problem E was on AtCoder: link.

even the submission that i didnt have time to submit is WA .. now I can rest in peace

I love this contest, where the difficulty is in ideas not just complex code.

When can we konw the final result ?

Just for curiosity, why are there no hacking session for this contes_- _t? The contests I participated since were rated for Div2 so... just curious.

So I was using ideone for this contest since I'm not home and I didn't want to install codeblocks on this pc and I got a message that bruce_knight copied my code for B. The message said I could be getting banned for this ? What are my options ?

Even tourist couldn't solve H ?
There must be something wrong with tourist or that question...