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basic_string::rbegin

Returns an iterator to the first element in a reversed string.

const_reverse_iterator rbegin( ) const;
reverse_iterator rbegin( );

Returns a random-access iterator to the first element in a reversed string, addressing what would be the last element in the corresponding unreversed string.

rbegin is used with a reversed string just as begin is used with a string.

If the return value of rbegin is assigned to a const_reverse_iterator, the string object cannot be modified. If the return value of rbegin is assigned to a reverse_iterator, the string object can be modified.

rbegin can be used to initialize an iteration through a string backwards.

// basic_string_rbegin.cpp
// compile with: /EHsc
#include <string>
#include <iostream>

int main( )
{
   using namespace std;
   string str1 ( "Able was I ere I saw Elba" ), str2;
   basic_string <char>::reverse_iterator str_rIter, str1_rIter, str2_rIter;
   basic_string <char>::const_reverse_iterator str1_rcIter;

   str1_rIter = str1.rbegin ( );
   // str1_rIter--;
   cout << "The first character-letter of the reversed string str1 is: "
        << *str1_rIter << endl;
   cout << "The full reversed string str1 is:\n ";
   for ( str_rIter = str1.rbegin( ); str_rIter != str1.rend( ); str_rIter++ )
      cout << *str_rIter;
   cout << endl;

   // The dereferenced iterator can be used to modify a character
    *str1_rIter = 'A';
   cout << "The first character-letter of the modified str1 is now: "
        << *str1_rIter << endl;
   cout << "The full modified reversed string str1 is now:\n ";
   for ( str_rIter = str1.rbegin( ); str_rIter != str1.rend( ); str_rIter++ )
      cout << *str_rIter;
   cout << endl;

   // The following line would be an error because iterator is const
   // *str1_rcIter = 'A';

   // For an empty string, begin is equivalent to end
   if ( str2.rbegin( ) == str2.rend ( ) )
      cout << "The string str2 is empty." << endl;
   else
      cout << "The stringstr2  is not empty." << endl;
}
The first character-letter of the reversed string str1 is: a
The full reversed string str1 is:
 ablE was I ere I saw elbA
The first character-letter of the modified str1 is now: A
The full modified reversed string str1 is now:
 AblE was I ere I saw elbA
The string str2 is empty.

Header: <string>

Namespace: std

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