What is the difference between using a struct with two fields and a pair?

Question

What is the difference regarding memory allocation and efficiency between using a struct with two fields and a pair?

Answer 1

As this isn't mentioned above, if you want the benefits of your own name, but the advantages of std::pair (or any other objects), you can use "using" ( from c++11 onwards). You can set this in your namespace or class declaration.

In fact this is how many of my classes now start out...

using myPair = pair;

cf. C++ reference. for more documentation.