Useful Functions

The global functions std::begin, std::end, std::prev, std::next, std::distance and std::advance make your handling of the iterators a lot easier. Only the function std::prev requires a bidirectional iterator. All functions need the header <iterator>. The table gives you an overview:

Global function	Description
std::begin(cont)	Returns a begin iterator to the container cont.
std::end(cont)	Returns an end iterator to the container cont.
std::rbegin(cont)	Returns a reverse begin iterator to the container cont.
std::rend(cont)	Returns a reverse end iterator to the container cont.
std::cbegin(cont)	Returns a constant begin iterator to the container cont.
std::cend(cont)	Returns a constant end iterator to the container cont.
std::crbegin(cont)	Returns a reverse constant begin iterator to the container cont.
std::crend(cont)	Returns a reverse constant end iterator to the container cont.
std::prev(it)	Returns an iterator, which points to a position before it
std::next(it)	Returns an iterator, which points to a position after it.
std::distance(fir, sec)	Returns the number of elements between fir and sec.
std::advance(it, n)	Puts the iterator it n positions further.

Useful functions for iterators

Now, the application of the useful functions.