public member function

std::map::rbegin

<map>
      reverse_iterator rbegin();
const_reverse_iterator rbegin() const;
Return reverse iterator to reverse beginning
Returns a reverse iterator referring to the last element in the map container.

Internally, map containers keep their elements ordered by their key from lower to higher, therefore rbegin returns the element with the highest key in the map.

Notice that rbegin does not refer to the same element as end, but to the element right before it.

Parameters

none

Return Value

A reverse iterator to the reverse beginning of the sequence.

Both reverse_iterator and const_reverse_iterator are member types. In the map class template, these are reverse bidirectional iterators, defined as reverse_iterator<iterator> and reverse_iterator<const_iterator> respectively.

Dereferencing this iterator accesses the element's value, which is of type pair<const Key,T>.

Example

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// map::rbegin/rend
#include <iostream>
#include <map>
using namespace std;

int main ()
{
  map<char,int> mymap;
  map<char,int>::reverse_iterator rit;

  mymap['x'] = 100;
  mymap['y'] = 200;
  mymap['z'] = 300;

  // show content:
  for ( rit=mymap.rbegin() ; rit != mymap.rend(); rit++ )
    cout << rit->first << " => " << rit->second << endl;

  return 0;
}


Output:
z => 300
y => 200
x => 100

Complexity

Constant.

See also

map::rend
Return reverse iterator to reverse end (public member function)
map::begin
Return iterator to beginning (public member function)
map::end
Return iterator to end (public member function)