Where and why do you need to put the template and typename keywords in C++?

Hello colleagues! I've been writing in C++ for a few months now, but templates still give me a headache. Especially confusing are the `template` and `typename` keywords. I understand they are somehow related to dependent names, but in practice I keep getting compilation errors. Here's a specific example that broke me. Suppose I have a template container class, and I want to write a function that prints elements from a nested iterator type: ```cpp #include #include template void printFirst(const T& container) { T::const_iterator it = container.begin(); // Error! std::cout << *it << std::endl; } int main() { std::vector vec = {1, 2, 3}; printFirst(vec); return 0; } ``` The compiler (G