2. リファレンス
3. algorithm
4. reverse

最終更新日時: 2026年09月11日 13時06分31秒 (JST)
Akira Takahashi が更新

履歴 編集

std::ranges::reverse(C++20)

namespace std::ranges {
  template <bidirectional_iterator I,
            sentinel_for<I> S>
    requires permutable<I>
  constexpr I
    reverse(I first,
            S last); // (1) C++20

  template <bidirectional_range R>
    requires permutable<iterator_t<R>>
  constexpr borrowed_iterator_t<R>
    reverse(R&& r);  // (2) C++20

  template <execution-policy Ep,
            random_access_iterator I,
            sized_sentinel_for<I> S>
    requires permutable<I>
  I reverse(Ep&& exec,
            I first,
            S last); // (3) C++26

  template <execution-policy Ep,
            sized-random-access-range R>
    requires permutable<iterator_t<R>>
  borrowed_iterator_t<R>
    reverse(Ep&& exec,
            R&& r);  // (4) C++26
}

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

int main() {
  std::string str = "reverse";

  std::ranges::reverse(str);
  std::cout << str << std::endl;
}

esrever

#include <iostream>
#include <vector>
#include <algorithm>
#include <execution>

int main()
{
  std::vector<int> v = {1, 2, 3, 4, 5};

  // 並列に要素の並びを逆にする
  std::ranges::reverse(std::execution::par, v);

  for (int i : v) {
    std::cout << i << ' ';
  }
  std::cout << std::endl;
}

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