template<class BidirectionalIterator>
bool next_permutation(BidirectionalIterator first,
BidirectionalIterator last);
template<class BidirectionalIterator, class Compare>
bool next_permutation(BidirectionalIterator first,
BidirectionalIterator last, Compare comp);
Effects: Takes a sequence defined by the range [first,last) and transforms it into the next permutation. The next permutation is found by assuming that the set of all permutations is lexicographically sorted with respect to operator< or comp. If such a permutation exists, it returns true. Otherwise, it transforms the sequence into the smallest permutation, that is, the ascendingly sorted one, and returns false.
Requires: BidirectionalIterator shall satisfy the requirements of ValueSwappable ([swappable.requirements]).
Complexity: At most (last - first)/2 swaps.
template<class BidirectionalIterator>
bool prev_permutation(BidirectionalIterator first,
BidirectionalIterator last);
template<class BidirectionalIterator, class Compare>
bool prev_permutation(BidirectionalIterator first,
BidirectionalIterator last, Compare comp);
Effects: Takes a sequence defined by the range [first,last) and transforms it into the previous permutation. The previous permutation is found by assuming that the set of all permutations is lexicographically sorted with respect to operator< or comp.
Returns: true if such a permutation exists. Otherwise, it transforms the sequence into the largest permutation, that is, the descendingly sorted one, and returns false.
Requires: BidirectionalIterator shall satisfy the requirements of ValueSwappable ([swappable.requirements]).
Complexity: At most (last - first)/2 swaps.