[alg.random.shuffle]

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template<class RandomAccessIterator, class UniformRandomBitGenerator>
  void shuffle(RandomAccessIterator first,
               RandomAccessIterator last,
               UniformRandomBitGenerator&& g);

namespace ranges {
  template<RandomAccessIterator I, Sentinel<I> S, class Gen>
    requires Permutable<I> &&
             UniformRandomBitGenerator<remove_reference_t<Gen>>
    I shuffle(I first, S last, Gen&& g);
  template<RandomAccessRange R, class Gen>
    requires Permutable<iterator_t<R>> &&
             UniformRandomBitGenerator<remove_reference_t<Gen>>
    safe_iterator_t<R> shuffle(R&& r, Gen&& g);
}

Requires: For the overload in namespace std:

(1.1)
RandomAccessIterator shall meet the Cpp17ValueSwappable requirements ([swappable.requirements]).
(1.2)
The type remove_reference_t<UniformRandomBitGenerator> shall meet the uniform random bit generator ([rand.req.urng]) requirements.

Effects: Permutes the elements in the range [first, last) such that each possible permutation of those elements has equal probability of appearance.

Remarks: To the extent that the implementation of this function makes use of random numbers, the object referenced by g shall serve as the implementation's source of randomness.

24 Algorithms library [algorithms]

24.6 Mutating sequence operations [alg.modifying.operations]

24.6.13 Shuffle [alg.random.shuffle]