Any STL data structure like pair that gives three items(types) instead of two?

c++ data-structures c++11 std-pair
Arch1tect picture Arch1tect · Mar 31, 2013 · Viewed 20.4k times · Source

Question 1:

I'm using C++ 11, and I'm learning. I realize I can do this with two pairs:

pair<pair<<#class _T1#>, <#class _T2#>>, <#class _T3#>>

Is that the best way?

Question 2:

If I don't need different types, so same type for two items, is it a waste to use pair, what should I use then? For three items? (again same type)

Answer

Xymostech picture Xymostech · Mar 31, 2013

Use a std::tuple:

std::tuple<_T1, _T2, _T3>

Note that std::tuples support an arbitrary amount of types stored in them. Also, to access the elements, you can't do the nice pair.first/pair.second, you have to use the syntax std::get<n>(tuple), where n is the element you want to retrieve.

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