C++ string const_iterator

#include <iostream> 
#include <string> 

using namespace std; 

int main(int argc, char *argv [])
{   //from  w ww. j  a v a2  s  .  c  om
        string myString{ "This is my string!" }; 

        for (string::const_iterator iter = myString.cbegin(); iter != myString.cend(); ++iter) 
        { 
                cout << *iter << endl; 
        } 
          
        for (string::const_reverse_iterator iter = myString.crbegin(); iter != myString.crend(); ++iter) 
        { 
                cout << *iter << endl; 
        } 
        return 0; 
}