std::map<Key,T,Compare,Allocator>::rend, std::map<Key,T,Compare,Allocator>::crend

Since C++11

Returns a reverse iterator to the element following the last element of the reversed map. It corresponds to the element preceding the first element of the non-reversed map. This element acts as a placeholder, attempting to access it results in undefined behavior.

# Declarations

reverse_iterator rend();

(noexcept since C++11)

const_reverse_iterator rend() const;

(noexcept since C++11)

const_reverse_iterator crend() const noexcept;

(since C++11)

# Return value

Reverse iterator to the element following the last element.

# Notes

libc++ backports crend() to C++98 mode.

# Example

#include <chrono>
#include <iomanip>
#include <iostream>
#include <string_view>
#include <map>
 
using namespace std::chrono;
 
int main()
{
    const std::map<year_month_day, int> messages
    {
        {February/17/2023, 10},
        {February/17/2023, 20},
        {February/16/2022, 30},
        {October/22/2022, 40},
        {June/14/2022, 50},
        {November/23/2021, 60},
        {December/10/2022, 55},
        {December/12/2021, 45},
        {April/1/2020, 42},
        {April/1/2020, 24}
    };
 
    std::cout << "Messages received (date order is reversed):\n";
    for (auto it = messages.crbegin(); it != messages.crend(); ++it)
        std::cout << it->first << " : " << it->second << '\n';
}

# See also