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std::reverse_iterator<Iter>::operator++,+,+=,--,-,-= - cppreference.com

From cppreference.com

reverse_iterator& operator++();
(1) (constexpr since C++17) 
reverse_iterator& operator--();
(2) (constexpr since C++17) 
reverse_iterator operator++( int );
(3) (constexpr since C++17) 
reverse_iterator operator--( int );
(4) (constexpr since C++17) 
reverse_iterator operator+( difference_type n ) const;
(5) (constexpr since C++17) 
reverse_iterator operator-( difference_type n ) const;
(6) (constexpr since C++17) 
reverse_iterator& operator+=( difference_type n );
(7) (constexpr since C++17) 
reverse_iterator& operator-=( difference_type n );
(8) (constexpr since C++17)

Increments or decrements the underlying iterator reversely.

1,3) Decrements the underlying iterator.

2,4) Increments the underlying iterator.

5) Returns a reverse_iterator whose underlying iterator is advanced by -n positions.

6) Returns a reverse_iterator whose underlying iterator is advanced by n positions.

7) Advanced the underlying iterator by -n positions.

8) Advanced the underlying iterator by n positions.

Parameters

n - position relative to current location

Return value

1,2) *this

3,4) A copy of *this made before the change

5) reverse_iterator(base() - n);

6) reverse_iterator(base() + n);

7,8) *this

Example

#include <iostream>
#include <iterator>
#include <list>
#include <vector>

int main()
{
    std::vector v{0, 1, 2, 3, 4};
    auto rv = std::reverse_iterator{v.rbegin()};
    std::cout << *(++rv) << ' '; // 3
    std::cout << *(--rv) << ' '; // 4
    std::cout << *(rv + 3) << ' '; // 1
    rv += 3;
    std::cout << rv[0] << ' '; // 1
    rv -= 3;
    std::cout << rv[0] << '\n'; // 4
    
    std::list l{5, 6, 7, 8};
    auto rl = std::reverse_iterator{l.rbegin()};
    std::cout << *(++rl) << ' '; // OK: 3
    std::cout << *(--rl) << '\n'; // OK: 4
    // The following statements raise compilation error because the
    // underlying iterator does not model the random access iterator:
//  *(rl + 3) = 13;
//  rl += 3;
//  rl -= 3;
}

Output:

See also