std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>:: rend, std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>:: crend

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C++
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std::flat_map
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reverse_iterator rend ( ) noexcept ;
(1) (since C++23)
const_reverse_iterator rend ( ) const noexcept ;
(2) (since C++23)
const_reverse_iterator crend ( ) const noexcept ;
(3) (since C++23)

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

range-rbegin-rend.svg

Parameters

(none)

Return value

Reverse iterator to the element following the last element.

Complexity

Constant.

Example

Run this code 
#include <chrono>
#include <iomanip>
#include <iostream>
#include <string_view>
#include <flat_map>
 
using namespace std::chrono;
 
int main()
{
    const std::flat_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';
}

Possible output: 

Messages received (date order is reversed):
2023-02-17 : 10
2022-12-10 : 55
2022-10-22 : 40
2022-06-14 : 50
2022-02-16 : 30
2021-12-12 : 45
2021-11-23 : 60
2020-04-01 : 42

See also

returns a reverse iterator to the beginning
(public member function)
(C++14)
returns a reverse end iterator for a container or array
(function template)
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