std::array<T,N>::rbegin, std::array<T,N>::crbegin

iterator rbegin() noexcept;
 (1) (since C++11)
(constexpr since C++17) 
const_iterator rbegin() const noexcept;
 (2) (since C++11)
(constexpr since C++17) 
const_iterator crbegin() const noexcept;
 (3) (since C++11)
(constexpr since C++17)

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

range-rbegin-rend.svg

Parameters

(none)

Return value

Reverse iterator to the first element.

Complexity

Constant.

Example

#include <algorithm>
#include <array>
#include <iostream>
#include <string>
#include <string_view>
 
int main()
{
    constexpr std::array<std::string_view, 8> data = {"▁","▂","▃","▄","▅","▆","▇","█"};
 
    std::array<std::string, std::size(data)> arr;
 
    std::copy(data.cbegin(), data.cend(), arr.begin());
    //             ^              ^           ^
 
    auto print = [](const std::string_view s) { std::cout << s << ' '; };
 
    print("Print 'arr' in direct order using [cbegin, cend):\t");
    std::for_each(arr.cbegin(), arr.cend(), print);
    //                ^             ^
    print("\n\nPrint 'arr' in reverse order using [crbegin, crend):\t");
    std::for_each(arr.crbegin(), arr.crend(), print);
    //                ^^             ^^
    print("\n");
}

Output:

Print 'arr' in direct order using [cbegin, cend):        ▁ ▂ ▃ ▄ ▅ ▆ ▇ █
 
Print 'arr' in reverse order using [crbegin, crend):     █ ▇ ▆ ▅ ▄ ▃ ▂ ▁

See also

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

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