map::rbegin


public member function
      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)