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/C++std::span<T,Extent>::rend
constexpr reverse_iterator rend() const noexcept; | (since C++20) |
Returns a reverse iterator to the element following the last element of the reversed span. It corresponds to the element preceding the first element of the non-reversed span. This element acts as a placeholder, attempting to access it results in undefined behavior.
Parameters
(none).
Return value
Reverse iterator to the element following the last element.
Complexity
Constant.
Example
#include <algorithm>
#include <iostream>
#include <span>
#include <string_view>
void ascending(const std::span<const std::string_view> data,
const std::string_view term)
{
std::for_each(data.begin(), data.end(),
[](const std::string_view x) { std::cout << x << ' '; });
std::cout << term;
}
void descending(const std::span<const std::string_view> data,
const std::string_view term)
{
std::for_each(data.rbegin(), data.rend(),
[](const std::string_view x) { std::cout << x << ' '; });
std::cout << term;
}
int main()
{
constexpr std::string_view bars[]{ "▁","▂","▃","▄","▅","▆","▇","█" };
ascending(bars, " ");
descending(bars, "\n");
}Output:
▁ ▂ ▃ ▄ ▅ ▆ ▇ █ █ ▇ ▆ ▅ ▄ ▃ ▂ ▁
See also
|
(C++20) | 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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