The simplest container: std::array<T, N>

The simplest standard container class is std::array<T, N>, which behaves just like a built-in ("C-style") array. The first template parameter to std::array indicates the type of the array's elements, and the second template parameter indicates the number of elements in the array. This is one of the very few places in the standard library where a template parameter is an integer value instead of the name of a type.

Normal C-style arrays, being part of the core language (and a part that dates back to the 1970s, at that!), do not provide any built-in operations that would take linear time to run. C-style arrays let you index into them with operator[], and compare their addresses, since those operations can be done in constant time; but if you want to assign the entire contents of one C-style array to another, or compare the contents of two arrays, you'll find that you can't do it straightforwardly. You'll have to use some of the standard algorithms...