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You can use several words in query to find by all of them at the same time. In addition, if you are lucky search understands word forms and some synonyms. It supports search by title and author. Examples:
305— search for 305, most probably it will find blogs about the Round 305andrew stankevich contests— search for words "andrew", "stankevich" and "contests" at the same timeuser:mikemirzayanov title:testlib— search containing "testlib" in title by MikeMirzayanov"vk cup"— use quotes to find phrase as istitle:educational— search in title
Results
1.
codefoces
Last visit:
7 years ago
Registered:
7 years ago
2.
Randomized algorithms lecture, part 1 & 2 You can watch the lecture on Youtube: https://youtu.be/0r2D32esF3Y. I will do a second part soon. Some problems are quite vague, it's a nature of this topic.
1. Warm-up: You toss a coin till you get tails. How many tosses there will be, on average?
2. **X or smaller** — There is a hidden number $X$. An interactor repeatedly gives you a number, either $X$ or something smaller than $X$. All numbers are positive integers. When can you stop and say that you are (almost) certain what is the value of $X$?
3. **Line through N/4 points** — Given $N \leq 10^5$ points, find a line that passes through the maximum number of points. It's guaranteed that the answer is at least $N / 4$.
4. **GCD** ([problem:364D]) — given a set of $N \leq 10^6$ numbers, each up to $10^{12}$, find the maximum possible number that is a divisor of at least half of given numbers.
5. **ACTG prefix** — Guess a hidden string $S$ with characters A, C, T, G. You can choose some string and ask if...
3.
December Cook-Off CodeChef invites you to participate in [the December Cook-off 2014](http://www.codechef.com/COOK53).
**Time**: 21st December 2014 (2130 hrs) to 22nd December 2014 (0000 hrs). (IST — +5:30 GMT) — Check your [timezone](http://www.timeanddate.com/worldclock/fixedtime.html?msg=December+Cook-Off+2014&iso=20141221T1600&ah=2&am=30).
[Details](http://www.codechef.com/COOK53)
Registration</b>: Just need to have a CodeChef user id to participate.
New users can register <a target="_blank" href="http://www.codechef.com/user/register/">here</a>.
<br />
**Problem Setter**: [user:Rubanenko,2014-07-20]
**Problem Tester**: [user:tuananh93,2014-07-20]
**Russian Translators**: [user:vadimmm,2014-12-21] & [user:Rubanenko,2014-12-21]
**Editorialist**: [user:elfus0,2014-07-20]
**Mandarin Translator**: [user:xiaodao,2014-07-20]
It's my third CodeChef Cook-Off. The contest is quite balanced and I think that this contest will bring you something new and unusua...
4.
Fair Play Charter by Panathlon International Dear Codefoces Members,
I am writing this blog after reading several blogs in this website about events of unfair practices during recent Codeforces contests. I have been fortunate to read a long time ago the following Fairness Charter prepared by the [International Fair Play Committee](http://www.fairplayinternational.org/home) to promote fair practices during sports activities and to keep the spirit of real championship alive.
<spoiler summary="Fair Play Charter">
**Whatever is my role in sport, including that of a spectator, I undertake the following:**
1. To turn every sports meeting, irrespective of whatever is at stake and its importance, into a privileged moment, a happy event.
2. To conform to the rules and the spirit of the sport I practice.
3. To respect my opponents as I respect myself.
4. To accept the decisions of referees or sports judges well aware that, just like me, they have the right to make mistakes but they do their utmost to avoid th...
5.
What is the fastest known solution for the Counting Necklaces problem? Hello codefoces users.
A while ago, I solved CSES problem 2209 ([https://cses.fi/problemset/task/2209](https://cses.fi/problemset/task/2209)) related to combinatorics involving necklaces (https://en.wikipedia.org/wiki/Necklace_(combinatorics)) with a time complexity of O(sqrt(n) + divs(n) * (divs(n) + log(n))). I believe this complexity can be further reduced to O(sqrt(n) + divs(n) * (2^(nOfPrimes(n)) * log(divs(n)) + log(n))).
Upon reading the editorial, I discovered that the official solution utilizes Burnside's Lemma and has a time complexity of O(nlogn). I was unsure if my solution was previously known or not.
After conducting some research, I was unable to find a similar solution to mine. Consequently, I considered using this problem with higher constraints in a future contest. However, I am uncertain whether this is a wise decision. Therefore, I have two questions:
1. Is there a known solution with a better time complexity for this problem than my approach?
2. Would ...
6.
What to do for query problems? Howdy Codeforces!
Recently, while solving previous Codefoces problems, I have seen many query problems. What I mean by query problems are: you are given q queries, like updating and printing something.
This is what I have gathered from query problems:
- Arrays can be used for simple query problems.
- Prefix sums can sometimes be used for query problems (No Updates Ranged Query)
- Sets/Multisets are often used for query problems that need O(logn) operations.
- Ordered set is used for some query problems (Point Update Range Query)
- Segment tree (with lazy propagation on ranged updates) can be used often for Point Update Range Query, Range Update Point Query, Range Update Range Query.
Of course, although segment tree is a solution for many query problems, it isn't easy to code, especially for specialists like me.
Me personally, I have started to direct myself to thinking set/multiset first, because it seems to often work.
Did I miss any ways to solve query problems?
...
7.
Predict: myee will reach 4000000000000000 in 1 year. ## [Origin：](https://codeforces.me/blog/entry/120544)
As we have witnessed, in the recently concluded **myee Round 114514**,[user:myee,2023-09-21] achieved the 0st place.
In fact it was the 114514th time that he got rank#1 in myee: rank#1 in the myee Round 1919810.
This is only what he has achieved on Codeforces; when we examine his achievements in other areas, we can still be surprised.
For example, on the myeeCoder, he has been rank#1 in AmyeeC for 114514000 times yet.
He has been the youngest LGMyee in the history of Codeforces so far. (I means the age when he reached LGMyee. Sorry for the confusion it has made.)
In the ZJOI 2024, he reached rank 1 in Zhijiang, one of the best provinces on CP in China.
In the CNOI 2025, he got 999pts in the 1st place, while the one in the 2nd place got only 0(999pts less than him!), which is amazing.
In the near future, he'll definitely represent China in participating in the IOI.
From ISIJ to APIO, from Codefoces to At...
8.
Can someone find the magic? Hello,
on today's Educational Round I came across a problem that made me a bit sad..
On the problem [Two Seals](http://codeforces.me/contest/837/problem/C) I submitted this [code](http://codeforces.me/contest/837/submission/29165139).
As you can see, on the third input it fails. But when I run this code on my machine with the following CLI
`g++ -o [object] [code.cpp] -std=c++11 -Wfatal-errors`
It returns me the correct answer for this test case. Can someone help me figure out what am I missing on CLI or compiler option here on codefoces (So I can prevent myself from doing it again) ?
It really made me sad, what if it was a rated round ? My dreams would have been crushed.
Thank you for your time.
**PS:** I'm using `GNU C++14` here on codeforces.
9.
Rating Distribution for Div-2-A,B,C problems As the title suggests i used the codefoces api and did some python coding to find the average and median ratings for Div 2,A,B,C problems ,which i believe will help in newbies like me to grow.
Here are the results:
-This shows the spread of the problem ratings .
-This shows boxplot
10.
How to be a Legendary Grandmaster?(temporary） Legendary Grandmaster is many coders' dream.
But it's not easy to be a Legendary Grandmaster.
How can we beLegendary Grandmaster?
Every Christmas,login Codeforces.[Open you profile](http://codefoces/profile/{your%shandle})
Choose 'Magic',the follow the santa.Finally choose 'Legendary Grandmaster'or other you want.
After that you'll became a Legendary Grandmaster,even though your rating is 0.
remember it is temporary,so if you've done it successful,take a photo of your profile first.
11.
Math Math Math Hello everyone, I wonder if working on Project Euler will help us to be good at math and thinking in competitive programming. I admire the Chinese people because they are very good at math and I want to be too. And I find that most people who are good at Math are usually quite easy to get high rank in Codefoces competitions, that's my personal opinion. And let me ask if there is a contest for us to practice Math from basic to advanced in programming and people's reviews about the Project Euler website. Thanks.
12.
Thank you, codefoces Thank you, codeforces. thank you for providing us with a platform for the competition. I come from a school that doesn't put much emphasis on computer competitions, and it was codeforces that gave me the opportunity to participate in computer competitions. The competitions here are really good and I enjoy the informatics Olympiad. I would like to express my sincere thanks to codeforces!
13.
Need some advise, please.. Hello everyone..
I am trying to prepare for IOI 2023. if there is anyone who has already participated in IOI please give me some advise.
My limit is 1200 level problems. I can't overcome my limits but I am still trying to practice.
What should be my minimum rating in Codefoces So that I can at least win a Silver Medal..
14.
Different result in my compiler This is very simple problem: 266B — Queue at the School.
But somehow the codefoces compiler tells that i got wrong answer (BGGBG), although in my compiler it is right(GBGGB).
import java.util.Scanner;
public class Codeforces {
public static void main(String[] args) {
Scanner scn = new Scanner(System.in);
int n = scn.nextInt();
int t = scn.nextInt();
String str = scn.next();
char[] chr = str.toCharArray();
boolean chng = true;
for(int ti = 1; ti <= t && chng; ti++){
chng = false;
for(int ni = 0; ni < n - 1; ni++){
if(chr[ni + 1] == 'g' && chr[ni] == 'b'){
chr[ni + 1] = 'b';
chr[ni] = 'g';
ni++;
chng = true;
}
}
}
for(int i = 0; i < n; i++){
System.out.print(chr[i]);
}
}
}
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