Code walkthrough

The following line declares an array of a fixed size (5) and initializes the array with five elements:

array<int,5> a = { 1, 5, 2, 4, 3 };

The size mentioned can't be changed once declared, just like a C/C++ built-in array. The array::size() method returns the size of the array, irrespective of how many integers are initialized in the initializer list. The auto pos = a.begin() method declares an iterator of array<int,5> and assigns the starting position of the array. The array::end() method points to one position after the last element in the array. The iterator behaves like or mimics a C++ pointer, and dereferencing the iterator returns the value pointed by the iterator. The iterator position can be moved forward and backwards with ++pos and --pos, respectively.