The Modern C++ Challenge

15. IPv4 data type

The problem requires writing a class to represent an IPv4 address. This is a 32-bit value, usually represented in decimal dotted format, such as 168.192.0.100; each part of it is an 8-bit value, ranging from 0 to 255. For easy representation and handling, we can use four unsigned char to store the address value. Such a value could be constructed either from four unsigned char or from an unsigned long. In order to be able to read a value directly from the console (or any other input stream) and be able to write the value to the console (or any other output stream), we have to overload operator>> and operator<<. The following listing shows a minimal implementation that can meet the requested functionality:

class ipv4{ std::array<unsigned ...