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!
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?
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