Re: Confusion with iterator

"pandit" <jalaf28@gmail.com> wrote in message
news:82f808f4-aa38-4139-b456-3cd82afd6b76@d21g2000prf.googlegroups.com...


iterators are for _iterating_ through a container. I wouldn't worry about
how they work, but I'd learn how to use them.
Just think of it as a "special" kind of pointer to an element in a
container. You do not know how the underlying implementation of the
container works, so they provide you with a way to access an element no
matter how it has been allocated.

Almost all stl containers have a begin() and end() method.

If you visualize your stl container like an array, then begin points to
element [0] and end points to the next element out of bounds.

example:

#include<vector>
#include <iostream>

int main()
{
   std::vector<int> bunchonumbers;

   // Fill it up with numbers
   for(int i =0; i < 5; i++)
       bunchonumbers.pushback(i);

  // Visualize an array [0][1][2][3][4]

  // Now you can _iterate_ through it

  // begin points to element [0]
  // end points to some memory after [4], containing something unknown
  // notice how you can perform arithmetic just like pointers: it++
  for( std::vector<int>::iterator it = bunchonumbers.begin(); it !=
bunchonumbers.end(); it++)
  {
      // Notice how you can dereference the iterator just like a pointer
      std::cout << *it;
   }

   return 0;
}

Iterators are just a special way of accessing elements in a container.
There is more to iterators than that, but it is the basics. For example,
there are different flavors of iterators with different rules, but that
comes later.