AmericanPsycho's blog

By AmericanPsycho, history, 17 months ago, In English,

Why in the suffix array is it necessary to put a character like '$' in the end?
I do not understand why it does not work if that character is missing!
Thanks in advance!

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By AmericanPsycho, history, 18 months ago, In English,

Hi everyone

I need help with this knapsack variant
Thanks

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By AmericanPsycho, history, 19 months ago, In English,

Hi everyone

What data structures are needed in competitive programming?
I know all stl structures, segment tree and BIT. But I have heard
others like treap, AVL tree, persistents, but I don't know if those
structures are really neccesary for competitive programming or
all their uses can be replaced by others and if not,
What are all the necessary data structures?

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By AmericanPsycho, history, 20 months ago, In English,

Someone who knows this subject. Could tell me where you studied it?
And recommend me some problems, please?

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By AmericanPsycho, history, 21 month(s) ago, In English,

Hi everyone.

Lately I've done some combinatorial problems. And I am wondering.
What methods are used to calculate the binomial coefficients?
What is the most effective?

I have used dynamic programming, although it is effective for many
queries and can be modulated with any number, the range is too limited.


When the number is a bit higher, I have used modular arithmetic
but I need to precalculate all factorials and is needed a prime number
as a module and really the range is not so large just 10 ^ 5 maybe.
If the problem have higher numbers, I'm lost

Can you tell me what techniques you use and when they can be used are?
I hope you can help me
Thank you

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By AmericanPsycho, history, 22 months ago, In English,

All I have read about flows is Edmonds Karp’s Algorithm, which works for maximum flow, but I have seen that there are better algorithms than this one, and there are different problems that maximum flow (like mincost, dinic and others), I would like a list of all the topics and algorithms that are useful for learning network flow!

Thanks in advance!

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