How do I avoid unnecessary copies in C++?

In C++, unnecessary copies can be avoided using several techniques. These include using references instead of passing objects by value, utilizing move semantics introduced in C++11, and employing efficient containers from the Standard Template Library (STL). Here are a few common strategies:

• Use References: When passing large objects to functions, use references to avoid copying.
• Use Move Semantics: Leverage move constructors and move assignment operators to transfer resources without copying.
• Use Smart Pointers: Instead of copying objects, consider using smart pointers like std::shared_ptr or std::unique_ptr for better resource management.
• Return by Value with Move Semantics: Returning large objects by value is often optimized with move semantics.