nerd's blog

By nerd, 10 years ago, translation, In English

Hi there!

Is it necessary to know regular expressions in competitive programming? If yes, then is there any good tutorial?

Thanks

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By nerd, 12 years ago, In English

Dear All,

How to access to i*th element of a set in c++ effectively (*O(1) or (logN))?

Thanks

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By nerd, 13 years ago, In English

Hi everybody!

I have one question related with Polygon System (codecenter.sgu.ru/polygon)

Is there any limit in memory while uploading zip-archive file of tests?! even if it will be 300Mb?

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By nerd, 13 years ago, translation, In English
Equation of a line in two dimensional plane is ax + by + c = 0

How to find coefficients {a, b, c}?

We can find them by simplifying and modifying this:


after:

(x - x1)(y2 - y1) = (y - y1)(x2 - x1)

x(y2 - y1) - x1(y2 - y1) = y(x2 - x1) - y1(x2 - x1)

(y2 - y1) * x + (x1 - x2) * y + y1(x2 - x1) + x1(y2 - y1) = 0

a = y2 - y1
b = x1 - x2
c =  - by1 - ax1

It is all...

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By nerd, 13 years ago, translation, In English

Hi everybody!

Who knows where can I find videolections in dynamic with profile(that is by using bitwise operations and etc., something like mask)


Thanks...

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By nerd, 13 years ago, In English
When and where problems from current Petrozavodsk 2011 will be available to solve?!
And where I can find previous years problems?!

thanks.

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By nerd, 13 years ago, In English

In which problems we can use solving System of algebraic linear equations, such as by Gauss' method?

Is there any problems(not theoretical)?

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By nerd, 13 years ago, In English
Night of al-Qadr

The night of qadr is the most virtuous night of the year.  Allaah says in the Quran (what means):“We revealed it on the night of power [that is, qadr]." 


"What will tell you what the night of power is? It is better than a thousand months” [97:1-3] Any action, for example, reciting the Quran, making remembrance of Allaah, and so on, on the night of qadr is better than the same act performed for one thousand months.


P.S. Please, let's comment without any discrimination of religions.

P.S.S. Sorry for my poor english.

P.S.S.S. If you don't like this article, please ignore this! Thanks for understanding.

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By nerd, 13 years ago, In English

Let's watch Football match

  ...Real Madrid vs Barcelona...


Who can predict result of this match by using combinatorial formulas???

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By nerd, 13 years ago, In English
Who knows, where i can run any program, for example:
I wrote in C++ program, which checks, if number N is prime or not.
Then I have *.exe/*.sh file. Is there any web sites, where i can run that file, and server in that site is fast.
For example, in ideone.com how many operations done in one second, i mean speed of CPU.
So, is there any sites, where we can run our program, and speed of CPU in server of site is too fast, so that 109-1010 operations work in 1 - 2 seconds.

thanks...

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By nerd, 13 years ago, translation, In English

Please Help!


phi(N) = euler's function = x

how we can find N, when we are given x. let's name it like phi_inv(x) = N

for example: 

phi_inv(4) = 5, because phi(5) = 4.

x ≤ 1010

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By nerd, 13 years ago, In English

WELCOME To Everyone!!!

Recently I've learned MaxFlow, MinCostMaxFlow and Matching...

Where can I solve problems in matching?

Thanks...

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