Halit's blog

By Halit, history, 4 months ago, In English

Hello codeforces, Please, give information about Codeforces accounts of EJOI 2020 participants from your country.

UPD: I create a list of participants(I'll add all participants in comments), you can visit here

Copy-Pasted :)

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By Halit, history, 4 months ago, In English

Hi codeforces!

2 months ago I post a blog about goto for escaping from loops. Now I learn new thing about escaping(with lambda expressions)

folowing code for only escaping from loops

[&]{
    for(int i = 1;i <= n;i++){
	for(int j = 1;j <= n;j++){
	      if( condition )
                return;
	}
    }
}();

but you can use different ways like followings:

bool escaped = [&]{
   for(int i = 1;i <= n;i++){
	for(int j = 1;j <= n;j++){
	      if( condition )
                return true;
	}
    }
    return false;
}();

cout << (escaped ? "NO" : "YES" );

or you can use like function(it doesn't matter normal function or lambda function)

auto control =[&] -> bool {
   for(int i = 1;i <= n;i++){
	for(int j = 1;j <= n;j++){
	      if( condition )
                return true;
	}
    }
    return false;
}

cout << (control() ? "NO" : "YES" );

So what is your idea; using functions, lambda expressions, flags or goto?

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By Halit, history, 6 months ago, In English

Hi!

I learnt goto keyword in C++. But I couldn't see any code with using goto. So Why I shouldn't use goto? I want to use for this situation:

for(int i = 1;i <= n;i++){
   for(int j = 1;j <= n;j++){
       //some codes
       if(break all fors)
         goto q;
       //some codes
   }
}
q:

When I don't know goto keyword I am doing like this:

for(int i = 1;i <= n;i++){
   bool br = false;
   for(int j = 1;j <= n;j++){
       //some codes
       if(break all fors){
         br = true;
         break;
       }
       //some codes
   }
   if(br)
      break;
}

It's easy to see second code is longer.So why anyone doesn't use goto keyword?

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By Halit, history, 7 months ago, In English

Hello Codeforces!

We are excited to invite you to Preparing for Olympiads Contest Round #2 (LINK IS HERE)

  • You have 5 problems and 2 hours to solve it. Start time is here, registration will start 6 hours before the start of the contest.

  • Thanks to Writers; Halit, OsmanliTokadi and farukkastamonuda

  • Also thanks to otaliptus for translating the problems

UPD : Editorial is here

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By Halit, history, 8 months ago, In English

Hi Codeforces!

There is a lot of participants in contests. This is a good thing but I think servers aren't enough to handle it. Also, that creates "Queueforces" in contests. I think that issue must be handle(We must have good solutions, not like doing weak and very small pretest)... (MikeMirzayanov, please...)

If you have a solution to this topic(to decrease participants/ maybe new divisions?). Please, comment it. We can discuss it and MikeMirzayanov can see it...

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By Halit, history, 8 months ago, In English

Hi Codeforces!

I want to share some resources about Competitive Programming(books, websites) which shared by USACO. If you want to look you can go this address

COMPUTATIONAL PROBLEM-SOLVING BEFORE LEARNING TO CODE

Bebras Contests

Bebras Contests USA Version

CS Unplugged

LEARNING TO CODE

code.org

TechPrep by Facebook

IT-oLogy

Scratch

AppInventor

Code Academy

Khan Academy

BOOKS ON COMPETITIVE PROGRAMMING

Competitive Programming by Steven and Felix Halim

Programming Challenges by Steven Skeina and Miguel Revilla

Looking For a Challenge by a group of authors associated with the Polish Olympiads

BOOKS ON ALGORITHMS

Introduction to Algorithms by Cormen, Leiserson, Rivest, and Stein

Algorithm Design by Kleinberg and Tardos

The Algorithm Design Manual by Skiena

Algorithms by Sedgewick and Wayne

ONLINE SITES AND DISCUSSION FORUMS

Geeksforgeeks

IOI Community Site

This Codeforces Blog Entry

VplanetCoding by Riya Arora

Site by Benjamin Qi

PROBLEM ARCHIVES

USACO Problems

IOI tasks until 2007

UVa Online Judge

Sphere Online Judge

WCIPEG Online Judge

OTHER CONTEST

International Olympiads in Informatics -IOI-

Central European Olympiad in Informatics -CEOI-

Balkan Olympiad in Informatics -BOI-

Baltic Olympiad in Informatics -also called BOI-

Asia-Pacific Informatics Olympiad -APIO-

French-Australian Regional Olympiad -FARIO-

Other National Contest like USACO

University of Central Florida High-School Programming Contest

Carnegie Mellon Informatics and Mathematics Competition

Virginia Tech High School Programming Contest

Philadelphia Classic

American Computer Science League

ACM International Computer Problem-Solving Contest

TopCoder

Codeforces

Codechef

Google Code Jam

Calendar for Upcoming-Contest

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By Halit, history, 8 months ago, In English

Hi Codeforces!

I want to buy some Math, Algorithm and Competitive Programming books. If you know some good books, can you comment it?

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By Halit, history, 8 months ago, In English

Hi! I have a question. "Will EJOI 2020 Cancel Because COVID-19"? Is there any announcement for this topic?

UPD : I know about IOI's announcement but I couldn't found any EJOI announcement. I am waiting it since several months.

UPD_2 :

EJOI's announcement

UPD 3 : EJOI 2020 will be an Online Competition on 2-6 September

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By Halit, history, 9 months ago, In English

Hi --

Which one is better DFS/BFS. Someone says it can be change problem to problem. But I want to learn which type of problems are good for DFS, which type of problems are good for BFS?

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By Halit, history, 9 months ago, In English

Hello!

I have a question. I see some codes (some tourist codes) which includes Classes. Is it Useful or waste of time in Competitive Programming?

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