23 Algorithms library [algorithms]

23.6 Mutating sequence operations [alg.modifying.operations]

23.6.13 Shuffle [alg.random.shuffle]

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

Requires: RandomAccessIterator shall satisfy the Cpp17ValueSwappable requirements ([swappable.requirements]).

The type remove_reference_t<UniformRandomBitGenerator> shall satisfy the requirements of a uniform random bit generator ([rand.req.urng]) type whose return type is convertible to iterator_traits<RandomAccessIterator>::difference_type.

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

Complexity: Exactly (last - first) - 1 swaps.

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