iterator begin() const;
iterator end() const;
1) Returns an iterator to the first element of the path. If the path is empty, the returned iterator is equal to end().
2) Returns an iterator one past the last element of the path. Dereferencing this iterator is undefined behavior.
The sequence denoted by this pair of iterators consists of the following:
1) root-name (if any)
2) root-directory (if any)
3) sequence of file-names, omitting any directory separators
4) If there is a directory separator after the last file-name in the path, the last element before the end iterator is a fictitious dot file name.
 Return value
1) Iterator to the first element of the path.
2) Iterator one past the end of the path
May throw implementation-defined exceptions.
Examining the path "C:\users\abcdef\AppData\Local\Temp\" through iterators gives "C:" "/" "users" "abcdef" "AppData" "Local" "Temp" "."