Function templates in C++ enable the creation of functions that can operate on different data types without having to rewrite the entire function for each type. This promotes code reusability and reduces redundancy.

The std::vector container provides constant time (O(1)) access to elements using random access iterators. However, insertions (especially in the middle or at the beginning) might take linear time (O(n)) as elements need to be shifted to make space for the new element.

When an exception of Derived type is caught as its base type, using dynamic_cast can help determine the exact type of the caught exception. This can be useful if you want to take specific actions based on the exact type of the exception. Remember, dynamic_cast will return a nullptr if the cast is not valid for pointers or throw a std::bad_cast exception for references, so it's essential to check for these cases.

Instantiating a class template with a type that doesn't meet the template's requirements would result in a compilation error. Templates rely on the types they are instantiated with to adhere to specific criteria. If those criteria aren't met, the compiler will produce an error message indicating the discrepancies.

The do-while loop is designed to execute its block of code at least once before checking the condition. This ensures that the loop body runs even if the condition is false from the start.

While the use of "goto" is generally discouraged in modern programming due to making code harder to read and maintain, there are rare cases, like breaking out of multiple nested loops or complex error handling before exceptions were widely adopted, where its use might be considered.

Function templates can increase both compilation times and the size of the binary due to multiple instantiations for different data types. One way to address these concerns is by reducing unnecessary template instantiations, making sure only required instantiations are compiled, and using techniques like explicit instantiation.

Inline functions in C++ are expanded at the place where they are called, rather than being invoked. Because of this, they cannot be virtual as the virtual mechanism relies on function calls.

A common memory leak scenario is when an exception is thrown before the memory allocated dynamically (usually with new) is deallocated. If the exception prevents a destructor or a delete statement from being reached, the memory is never released, resulting in a memory leak.

The primary purpose of enum (short for "enumeration") in C++ is to create user-defined data types where you can define a set of named integer constants. It provides a way to assign names to integral constants, which makes a program easier to read and maintain.