| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // <algorithm> |
| |
| // template<RandomAccessIterator Iter, StrictWeakOrder<auto, Iter::value_type> Compare> |
| // requires ShuffleIterator<Iter> |
| // && CopyConstructible<Compare> |
| // constexpr void // constexpr in C++20 |
| // partial_sort(Iter first, Iter middle, Iter last, Compare comp); |
| |
| #include <algorithm> |
| #include <cassert> |
| #include <functional> |
| |
| #include "test_macros.h" |
| #include "test_iterators.h" |
| #include "MoveOnly.h" |
| |
| template<class T, class Iter> |
| TEST_CONSTEXPR_CXX20 bool test() |
| { |
| int orig[15] = {3,1,4,1,5, 9,2,6,5,3, 5,8,9,7,9}; |
| T work[15] = {3,1,4,1,5, 9,2,6,5,3, 5,8,9,7,9}; |
| for (int n = 0; n < 15; ++n) { |
| for (int m = 0; m <= n; ++m) { |
| std::partial_sort(Iter(work), Iter(work+m), Iter(work+n), std::greater<T>()); |
| assert(std::is_sorted(work, work+m, std::greater<T>())); |
| assert(std::is_permutation(work, work+n, orig)); |
| // No element in the unsorted portion is greater than any element in the sorted portion. |
| for (int i = m; i < n; ++i) { |
| assert(m == 0 || !(work[i] > work[m-1])); |
| } |
| std::copy(orig, orig+15, work); |
| } |
| } |
| |
| { |
| T input[] = {3, 4, 2, 5, 1}; |
| std::partial_sort(Iter(input), Iter(input + 3), Iter(input + 5), std::greater<T>()); |
| assert(input[0] == 5); |
| assert(input[1] == 4); |
| assert(input[2] == 3); |
| assert(input[3] + input[4] == 1 + 2); |
| } |
| return true; |
| } |
| |
| int main(int, char**) |
| { |
| int i = 42; |
| std::partial_sort(&i, &i, &i, std::greater<int>()); // no-op |
| assert(i == 42); |
| |
| test<int, random_access_iterator<int*> >(); |
| test<int, int*>(); |
| |
| #if TEST_STD_VER >= 11 |
| test<MoveOnly, random_access_iterator<MoveOnly*>>(); |
| test<MoveOnly, MoveOnly*>(); |
| #endif |
| |
| #if TEST_STD_VER >= 20 |
| static_assert(test<int, random_access_iterator<int*>>()); |
| static_assert(test<int, int*>()); |
| static_assert(test<MoveOnly, random_access_iterator<MoveOnly*>>()); |
| static_assert(test<MoveOnly, MoveOnly*>()); |
| #endif |
| |
| return 0; |
| } |