9 Iterators library [iterators]

9.7 Iterator adaptors [iterators.predef]

9.7.1 Reverse iterators [iterators.reverse]

9.7.1.2 reverse_iterator operations [reverse.iter.ops]

9.7.1.2.9 operator+= [reverse.iter.op+=]

constexpr reverse_iterator& operator+=(difference_type n) requires RandomAccessIterator<I>;

Effects: current -= n;

Returns: *this.