# std::flat_multimap<Key,T,Compare,KeyContainer,MappedContainer>::rbegin, std::flat_multimap<Key,T,Compare,KeyContainer,MappedContainer>::crbegin

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< cpp‎ | container‎ | flat multimap

reverse_iterator rbegin() noexcept; | (1) | (since C++23)
const_reverse_iterator rbegin() const noexcept; | (2) | (since C++23)
const_reverse_iterator crbegin() const noexcept; | (3) | (since C++23)

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

### Parameters

(none)

### Return value

Reverse iterator to the first element.

### Complexity

Constant.

### Notes

The underlying iterator of the returned reverse iterator is the end iterator. Hence the returned iterator is invalidated if and when the end iterator is invalidated.

### Example

Run this code

    #include <algorithm>
    #include <iostream>
    #include <string>
    #include <flat_map>

    int main()
    {
        std::flat_multimap<std::string, int> map
        {
            {"█", 1},
            {"▒", 5},
            {"░", 3},
            {"▓", 7},
            {"▓", 8},
            {"░", 4},
            {"▒", 6},
            {"█", 2}
        };

        std::cout << "Print out in reverse order using const reverse iterators:\n";
        std::for_each(map.crbegin(), map.crend(),
            [](std::pair<const std::string, int> const& e)
            {
                std::cout << "{ \"" << e.first << "\", " << e.second << " };\n";
            });

        map.rbegin()->second = 42; // OK: non-const value is modifiable
    //  map.crbegin()->second = 42; // Error: cannot modify the const value
    }

Possible output:

    Print out in reverse order using const reverse iterators:
    { "▓", 8 };
    { "▓", 7 };
    { "▒", 6 };
    { "▒", 5 };
    { "░", 4 };
    { "░", 3 };
    { "█", 2 };
    { "█", 1 };

### See also

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

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