Target audience: newbies and pupils (rating up to 1400).

Group link: https://codeforces.com/group/yg7WhsFsAp/contests (hit "join" on the right).

Hi. Enjoy a series of 8 problem lists for beginners. The example topics are strings, arrays, math, and binary search. You are allowed to discuss anything with others, or just look up solutions online. There are also 3 exams, each recommended for a 2-hour individual virtual participation. Use the displayed order, e.g. take exam 1 after day 3. It all should take you 2 weeks of intense bootcamp-like work (or a few months if you take your time).

The problems were originally used two years ago in a Saudi Arabia camp. It's a mix of around 70 existing CF problems and 30 new original problems, mainly prepared by kostka, with some help from me and mustafabar. I asked them for permission to publish everything.

I will put hints to some problems in this blog (or in the group? not sure). Expect a few videos and/or streams for beginners too. You should also read two first chapters of Competitive Programmer's Handbook.

UPD: On Sunday evening I'm making a stream with explanations to a few hard problems: P8, P11, P18, P30, P31, P33. You can try it with hints first:

**P08. Cashier**

**P11. Queens attack!**

**P18. Mountain peaks**

**P30. Temporarily unavailable**

**P31. Shuffle Hashing**

**P31. Shuffle Hashing, hint 2**

**P33. Thanos Sort**

Thanks a lot :D I'll try to solve all of them in the upcoming days

It is really usefull

Can those not in the rating range specified above not submit ?

Edit : Just checked, they can

You are allowed, but the problems should be easy and boring for you.

Awesome!!!!

you mind putting some more tough questions in there .

These are problems from a camp two years ago. The participants were beginners just after learning basic C++.

ohk i got it

This will help me a lot!

thanks a lot

Can you prepare

another one for 1400 to 1600?I will be very helpful! And thanks for preparing this one. I will submit these problems.Awesome

There is no problem numbered P17 in day 2

Oh, you are right. I see now that we removed it back then because it required an algorithm that participants didn't know yet. It was 1041B - Buying a TV Set.

I've renumerated problems.

Thanks for this bootcamp Errichto , Can we expect more such bootcamps with a certain level up anytime :) .

Reminds me of whenever I say I should start over competitive programming from the beginning since I am not good at the basics.

Hey!! Thanks a lot, it will surely help a lot.

Great , it will help us a lot.

I have just finished the basics of java and solved 100 URI basic problems and some hackerrank easy problems. need to read the first two chapters of "Competitive Programmer's Handbook". it will take some time. I will try it.

I have a question. if someone wants to try it after 3/4 months will these problems will be there?

Sure. I don't plan to ever hide these problems.

Hi It says "You are not allowed to take part in the group contest" if i click register.

You have to join the group first. See the page's right side and you'll see "Join Group" in this (https://codeforces.com/group/yg7WhsFsAp/contests) link.

thank you

thank you so much

Thanks a lot. Please arrange more Bootcamp or practice sessions like this for newbies.

Really awesome. I hope I enjoy and learn.I am really grateful for it.

When I try to register it says "you are not allowed to enter", I am new to this platform. how to register for this.

Actually it says " You are not allowed to take part in the group contest "

Come on. Read the top of the blog. Or just scroll up by a few comments.

First you gotta join the group using this -> https://codeforces.com/group/yg7WhsFsAp/contests. Then you can register!

where will i find the editorial of practice problem of day 1

Any hints/tips on how to solve P48 The line problem

The hint is in the original question already. It gave an unnecessary/redundant information which could have been omitted.

hey there i am trying to solve Day 2 P13 lost rectangle problem for almost a day now and ain't able to come up with a possible solution nor could find anything on the interent to help, coud anyone please help my with some possible idea . I would be realy helpful.

https://codeforces.com/group/yg7WhsFsAp/contest/355493/problem/P13

Hint 1Prime is a big hint in itself.

Hint 2The Area

Ais made by two integer (as given) sides. So, using this fact you can determine that for any integer to be the height or breadth of rectangle, It should evenly divide theA.Hint 3Just find all the prime factors of

A, and then say for any factorp, we can treat it as 1 of the side of rectangle. Therefore, the other side is A/p. Now, you have both the side. Find the Perimeter using the same idea for all the factors ofA, and print minimum one to the result.You use one word incorrectly:

Spoiler"prime" -> "divisor"

If the area is 100, possible shorter side lengths are 1, 2, 4, 5, 10. These are divisors, not primes.

Oh yes, I meant the same thing just got confused with right terminology.

Thanks for the correction.

I cant solve it... :(

This bootcamp will last for how many days?

2 weeks from the day of start of each section

And what about topics? Only strings, arrays, math, and binary search?

Yes most of them are observation based as far as what i have seen so far

How much time would you recommend to try to solve one problem by yourself, before moving to editorials (stuck on p48)

How can I get all the solution of this boot camp problems ?? I would be very helpful for me... Thank you

I don't know if it is right to discuss it here, but it is related to a question in this bootcamp. do let me know if I am not supposed to ask or post anything here. I am new to this platform.

In a particular problem if I use.

`for(size_t i =0; i<=sqrt(n) ; i++) //The answer gets accepted`

is there any difference(in performance)? if yes then an explanation will be helpful.

`i * i`

overflows. You need to use`(long long) i * i`

.good joob errichto thanks bro for questions

can any one help me slove primes question 1(lost rectangle)

SpoilerA= l*b; safe to assume one of sides 1<=l<=10^6. so other side will be A/l. l has to divide A.

Solutionthanks alot man

How do u take minimum of something in C++? any idea?

i use java but in c++ just use min keyword in java it is Math.min(a,b) like wise in c++ just remove math

thanks bro

happy to help

can some one help me p22 divior count

You are correct but if you implement this you will get TLE :)

here is what I have done

This works it was just after 10-12 submission I realized, I didn't gave hint as it is useless here it is direct solution, Now you should think why this works.

I have also implemented what you said but it gave TLE.

damn, this works and it is too small. please tell why it works. this method is so good.

NICEE

THANKS MAN

Solutionwhy cant I see the solutions of others after day 1??

Thanks bro.

Needed something just like this. Thanks:)

some one please help in P27

someone help me solving [problem:P48]

P48

SolutionFibonacci

hey can any one help me with ((p24 bubble sort))) i know what it is i get the ans but in the output format an any one help me and((( p26 selection sort)) also

Spoilerloop inner and outer n-1 time and print at the end of the inner loop, once the swaps are done.

tired it i think im doing it wrong can u help me with the solution

hmm, ill just send a snippet to at least help for this one and then you'll be able to solve p26 also.

Spoilerthanks man

https://ideone.com/LwBYna https://codeforces.com/group/yg7WhsFsAp/contest/355494/problem/P27

WA5

i need help here , please

Corner Case : 5 1 1 1 1 1 Ranks can not be the same

Can anybody explain me virtual contest-1 last question?

In that we just want to take the maximum frequency element greedily and add frequency*frequency to the ans(as mentioned in the question for

eachcard), we keep on doing this till the summation of frequencies of cards!=k.My Submission here

So first we give the characters to toastman and then calculate coin for each character by frequency in cards given to toastman

Yes, we give the maximum frequency character to toast man first then coin calculation is done, for x characters of a type x*frequency of that character is added to the answer.