next - C++ Reference - cplusplus.com
https://cplusplus.com/reference/iterator/nextReturns an iterator pointing to the element that it would be pointing to if advanced n positions. it is not modified. If it is a random-access iterator, the function uses just once operator+ or operator-.Otherwise, the function uses repeatedly the increase or decrease operator (operator++ or operator--) on the copied iterator until n elements have been advanced.
std::next in C++ - GeeksforGeeks
https://www.geeksforgeeks.org/stdnext-in-cpp02.08.2017 · std::next in C++. std::next returns an iterator pointing to the element after being advanced by certain no. of positions. It is defined inside the header file . It does not modify its arguments and returns a copy of the argument advanced by the specified amount. If it is a random-access iterator, the function uses just once operator + or ...