What is the copy-and-swap idiom in C++?

Hello everyone! I'm learning C++ and trying to understand the correct way to write a copy constructor and assignment operator. I've read about the rule of three, but I often come across mentions of some "copy-and-swap" idiom. I have a simple class that manages dynamic memory: ```cpp class String { public: String(const char* str = "") { size = strlen(str); data = new char[size + 1]; strcpy(data, str); } ~String() { delete[] data; } // Copy constructor String(const String& other) { size = other.size; data = new char[size + 1]; strcpy(data, other.data); } // Assignment operator - this is where I have problems String& operator=(const String& other) { // How to pr