std::map<Key,T,Compare,Allocator>::rbegin, std::map<Key,T,Compare,Allocator>::crbegin

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Technical Specifications

 

Containers library

array (C++11)

vector

deque

forward_list (C++11)

list

set

multiset

map

multimap

unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

stack

queue

priority_queue

span (C++20)

 

std::map

Member functions

map::map

map::~map

map::operator=

map::get_allocator

Element access

map::at

map::operator[]

Iterators

map::beginmap::cbegin (C++11)

map::endmap::cend (C++11)

map::rbeginmap::crbegin (C++11)

map::rendmap::crend (C++11)

Capacity

map::empty

map::size

map::max_size

Modifiers

map::clear

map::insert

map::insert_or_assign (C++17)

map::emplace (C++11)

map::emplace_hint (C++11)

map::try_emplace (C++17)

map::erase

map::swap

map::extract (C++17)

map::merge (C++17)

Lookup

map::count

map::find

map::contains (C++20)

map::equal_range

map::lower_bound

map::upper_bound

Observers

map::key_comp

map::value_comp

Deduction guides(C++17)

 

reverse_iterator rbegin();		(until C++11)
reverse_iterator rbegin() noexcept;		(since C++11)
const_reverse_iterator rbegin() const;		(until C++11)
const_reverse_iterator rbegin() const noexcept;		(since C++11)
const_reverse_iterator crbegin() const noexcept;		(since C++11)

Returns a reverse iterator to the first element of the reversed map. It corresponds to the last element of the non-reversed map. If the map is empty, the returned iterator is equal to rend().

Parameters

(none)

Return value

Reverse iterator to the first element.

Complexity

Constant.

Example

Run this code

#include <iomanip>
#include <iostream>
#include <map>
#include <string_view>
 
int main() 
{
    const std::map<int, std::string_view> coins {
        {10, "dime"},
        {100, "dollar"},
        {50, "half dollar"},
        {5, "nickel"},
        {1, "penny"},
        {25, "quarter"}
        }; // initializer entries in name alphabetical order
    std::cout << "US coins in circulation, largest to smallest denomination:\n";
    for (auto it = coins.crbegin(); it != coins.crend(); ++it) {
        std::cout << std::setw(11) << it->second << " = ¢" << it->first << '\n';
    }
}

Output:

US coins in circulation, largest to smallest denomination:
     dollar = ¢100
half dollar = ¢50
    quarter = ¢25
       dime = ¢10
     nickel = ¢5
      penny = ¢1

See also

rend crend (C++11)

returns a reverse iterator to the end (public member function)