Can someone explain this code for me?

Question

set<pair<pair<long long, long long>, long long> > st;

Answer 1

Set is a template class, meaning it can take different params types without making a class for each. Read more about templates to understand :)

Answer 2

"This class couples together a pair of values, which may be of different types (T1 and T2). The individual values can be accessed through its public members first and second"
From cplusplus

Answer 3

BTW a set is a dynamic array(at lest it is in Java) that store objects without duplication.

Answer 4

what about the pair class? deletes duplicated types?

Answer 5

I don't really know, maybe a cpp guru can help, but my guess it's a hashmap, key-value like

Answer 6

I was right? Haha