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

From cppreference.com
< cpp‎ | container‎ | array

 
 
 
 
reverse_iterator rbegin() noexcept;
(1) (since C++11)
(constexpr since C++17)
const_reverse_iterator rbegin() const noexcept;
(2) (since C++11)
(constexpr since C++17)
const_reverse_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.

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

#include <algorithm>
#include <array>
#include <iostream>
#include <string>
#include <string_view>
 
void print(const std::string_view s) { std::cout << s << ' '; }
 
int main()
{
    const std::array<std::string_view, 8> data
    {
        "▁", "▂", "▃", "▄", "▅", "▆", "▇", "█"
    };
    std::array<std::string, 8> arr;
 
    std::copy(data.cbegin(), data.cend(), arr.begin());
 
    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);
}

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)
returns a reverse iterator to the beginning of a container or array
(function template)